2 nd Period Review Projects. LO 3.33: The student is able to use representation(s) and appropriate models to describe features of a cell signaling pathway.

2 nd Period Review Projects

LO 3.33: The student is able to use representation(s) and appropriate models to describe features of a cell signaling pathway. SP 1.4: The student can use representations and models to analyze situations or solve problems qualitatively and quantitatively.  Explanation: A cell signaling pathway can be described in 3 major stages: reception, transduction, and response. With reception, a ligand (signal molecule) binds to a receptor, either embedded in the plasma membrane or present within the cell. Different types of receptors include G-protein linked, where the binding of a ligand leads to the activation of the G-protein, tyrosine kinase, where a dimer is formed to activate other proteins, ligand-gated ion channels, and intracellular receptors, which are activated by steroid hormones that pass through the plasma membrane. Next in the pathway is transduction, the conversion of a signal towards a response. Here, signaling cascades relay messages. These cascades involve phosphorylation, the activation of a protein by the addition of a phosphate group. Second messengers are often present to facilitate further signal relaying: these include cAMP, IP3, and Ca2+. Also characteristic of transduction is signal amplification, where a single ligand can bring about a great response due to the building up of active members in the transduction pathway. After the cascade, a response is initiated. Responses may include gene activation, increased/decreased metabolism, cell division etc. All these features (receptors, transduction, 2 nd messengers, amplification) may be depicted in a figure like that to the right and to the bottom  Multiple Choice Question: http://mol-biol4masters.masters.grkraj.org/html/Cellular_Signal_Transduction2- Cell_Surface_And_Cytosolic_Receptors.htm  FRQ: Cell signaling represents a major part of eukaryotic bodily functions. Consider the basic model of a cell signaling pathway. a) The cell signaling pathway begins with reception. Identify and describe TWO kinds of receptors and elaborate on how they allow a signal to move towards transduction. b) Determine which of the following would be the most effective in producing the greatest cellular response and explain your choice. Direct introduction of a transcription factor Ligand binding to a receptor Introduction of a kinase that is active later in the phosphorylation cascade Which of the following best explains the model to the left? a)Signal amplification is occurring as a response of one cell induces a pathway of another type of cell. b)The specificity of cell signaling depends on differing receptors and relay molecules, along with cross talk and pathway branches. c)Steroid hormones are being structurally altered by a receptor embedded in the membrane to become relay molecules. This is done in 4 possible ways. d)Second messengers are formed to deactivate the relay molecules through phosphorylation https://hodnett-ap.wikispaces.com/Chapter+11+Cell+Communication

Answer Key Multiple Choice Answer: Which of the following best explains the model to the left? a)Signal amplification is occurring as a response of one cell induces a pathway of another type of cell. b)The specificity of cell signaling depends on differing receptors and relay molecule, along with cross talk and pathway branches. c)Steroid hormones are being structurally altered by a receptor embedded in the membrane to become relay molecules. This is done in 4 possible ways. d)Second messengers are formed to deactivate the relay molecules through phosphorylation Explanation: The particular proteins a cell possessed determines what signal molecules it responds to and the nature of that response. Pathways can include differing relay molecules, branching of pathways, cross talk (inhibition and activation), and differing receptors. A) is false because signal amplification is the building up of active proteins that makes a large response possible. C) is false because steroid hormones bind to intracellular receptors and are not molecularly altered. Finally, D) is false because second messengers are allosteric activators and the image does not support the claim at all. FRQ Answer: a)The types of receptors include G protein linked, tyrosine kinase, ligand-gated ion channel, and intracellular receptors. When a signal molecule binds to a G protein linked receptor, the receptor becomes activated as it changes structural shape. An inactive G protein binds to the cytoplasmic side of the activated receptor causing GTP to displace the GDP on the protein, effectively activating that protein. Once this is completed, the G protein can trigger the next step of the pathway. Tyrosine kinase receptors are originally individual polypeptides. Once a signal molecule binds, a dimer forms as the two are joined. Dimerization activates the tyrosine-kinase region and the phosphorylation of the receptor tails occurs with the use of ATP. After this step, the receptor is fully activated and is recognized by specific relay proteins; these proteins undergo a structural change and becomes activated in order to trigger the pathway. Ligand gated ion receptors function as a ligand binds to the receptor and opens the gate, allowing specific ions to flow through the channel. This change in concentration of the ions allowed in leads to a cellular response. Lastly, intracellular receptors exist in the cytoplasm of a cell; its ligand is a steroid hormone, nonpolar and small enough to pass through the plasma membrane. Once the ligand binds, the ligand-receptor complex enters the nucleus to directly stimulate the transcription of a gene. b)The most effective method of creating a large cellular response is simply the binding of a ligand to a receptor. This process activates relay proteins that take part in signal amplification. Amplification when a single ligand can activate millions of molecules during a cell’s response. This is due to the fact that once proteins are activated, mostly by phosphorylation, they remain active for long enough to process numerous substrates. Directly introducing a transcription factor would not activate the necessary proteins and introducing an activated version of a kinase that is use later in the cascade would not collect the vast number of activated complexes as starting at the beginning of the cascade would.

LO 2.42: The student is able to pose a scientific question concerning the behavioral or physiological response of an organism to a change in its environment. SP 3.1: The student can pose scientific questions. Explanation: Organisms are able to respond to their changing surroundings using a combination of behavioral and physiological methods. Plants respond to light through photoperiodism, in which some species only flower if they have been in darkness for a certain amount of time, and through phototropism, in which most plants grow toward a light source.. Some organisms, especially simple ones, display kinesis, the undirected movement in response to an external stimulus. Animals also display taxis, the directed movement in response to a stimulus. Bacteria exhibit chemotaxis, movement in response to chemicals in the surrounding environment. Fungi reproduce both sexually and asexually, but ideally both. Many organisms operate on circadian rhythms, regular cycles of physiological activity that are often regulated by external stimuli such as light and temperature. Humans are diurnal, primarily active during the day, and have a circadian rhythm that is roughly 24 hours. Other organisms, like bats, are nocturnal and are primarily active at night. Humans have numerous physiological and behavioral reactions to changing temperatures in an attempt to maintain homeostasis of internal body temperature. The evaporation of sweat secreted by sweat glands is cooling mechanism, while the rapid constriction of skeletal muscles, called shivering, produces body heat. Some animals, namely birds, migrate to warmer areas to survive the cold winter. Other endotherms go into hibernation, a torpor characterized by slow breathing, slow heart rate, and decreased metabolism in order to conserve energy. As shown in Figure 1 found in BIO TXTBK, both animals’ body temperatures and metabolic rates are fairly steady during warmer months, followed by a significant decrease with the onset of winter. Throughout the winter, these animals remain in a deep sleep with little activity besides short periodic arousals to consume food they stored before the winter. Hibernation was selected for because it is energy efficient and allows some animals to survive the winter. MC Question: A man has just ran 3 miles in 80° weather. Which of the following questions would be most relevant in understanding how he will cool down? A) How does the heart respond to increased body temperature? B) How do blood vessels respond to increased body temperature? C) How does blood pressure respond to decreased body temperature? D) How does the Central Nervous System respond to increased body temperature? FRQ: Organisms respond to changes in their environment through behavioral and physiological means. A) Identify three behavioral or physiological ways to increase body temperature in humans. B) A lamp is placed to the left of a small plant. What process will occur? Explain in detail how that process will occur. C) Explain the countercurrent heat exchange in endotherms. Why did natural selection favor this process? Figure 1

Answer Key FRQ: Homeostasis is the steady-state physiological condition of the body. Consider homeostasis in humans. A) Identify three behavioral or physiological methods to increase body temperature. B) Explain the process of returning to homeostasis following a stimulus of increased body temperature. C) Explain the countercurrent heat exchange in endotherms. Why did natural selection favor this process? A) Body temperature is increased through shivering, in which skeletal muscles contract rapidly in order to produce heat. Despite the use of some ATP, the heat produced by shivering is beneficial to returning to homeostasis. Another method is vasoconstriction, a process by which blood vessels constrict and divert blood into deeper tissue to minimize the release of heat through the skin surface. A third mechanism is a behavioral one. When humans feel cold, they can choose to move into sunlight for example, or move toward another external source of heat. B) The plant will display positive phototropism, the orientation toward a light source, in this case the lamp. The tip of the plant is the part that detects light. Therefore, a light-activated mobile chemical is released from the tip of the plant in order to cause a cell response that will orient the plant toward the light. With the activation of proton pumps, cell walls on the “dark” side of the plant become more acidic, causing the enzymatic cleaving of the cross- linking polysaccharides. This allows microfibrils to increase the extensibility of the cell walls. Water enters the cells causing them to expand and elongate, effectively curving the plant toward the light source. This process is beneficial because then the plant can more effectively carry out photosynthesis. C) One method of internal regulation by endotherms is the countercurrent heat exchange in mammals, in which heat is exchanged between outward flowing arterial blood and inward flowing venous blood. Thus, blood near the tips of extremities are much colder than the blood closer to the body core. The parallel, close contact structure of arteries and veins conserves energy through minimized heat loss in cold conditions. Natural selection favored this process because heat loss is minimized, so energy is conserved. Organisms that are best able to maintain homeostasis with the least energy expenditure are the most reproductively fit. MC Question: A man has just ran 3 miles in 80° weather. Which of the following questions would be most relevant in understanding how he will cool down? A) How does the heart respond to increased body temperature? B) How do blood vessels respond to increased body temperature? C) How does blood pressure respond to decreased body temperature? D) How does the Central Nervous System respond to increased body temperature? B) Is the correct answer because blood vessels respond to changing external temperatures in order to maintain a steady internal body temperature. In hot conditions, blood vessels dilate (vasodilation), increasing heat loss through the skin surface. In cold conditions, blood vessels constrict (vasoconstriction), sending blood into deeper tissues and reducing heat loss through the skin.

LO 2.30: The student can create representations or models to describe nonspecific immune defenses in plants and animals. SP 1.1: The student can create representations and models of natural and manmade phenomena and systems in the domain SP 1.2: The student can describe representations and models of natural and manmade phenomena and systems in the domain Explanation: The nonspecific immune system is the body’s innate system that protects against infections. The nonspecific external defense system in humans are elements composed of the skin, mucous membranes, coughing, and urine. The “second line” is made up of cells and proteins that attack pathogens, but do not have memory. This would include agents like the inflammatory response, leukocytes, and the complement system. Plants have a similar structure because they also use physical barriers( cell walls), enzymes that perturb pathogens, and macrophages. Plants also do not have the specific immune system response, and this evolutionary adaptation is beneficial because plants are regenerative. The Evolutionary adaptation of the nonspecific immune system is to allow the body to rid itself of pathogens and do so quickly, but the only down side is there is no memory. MC Question: Which of the following would be classified as the best form of the first line of nonspecific immune responses? a.The natural killer cells perforate the cells by releasing the protein perforin b.Using the polio vaccine to help combat against the loss of motor function c.The stomach acid pH eating away bacteria that enters that region of the body d.The T cells attacking the abnormal growth of cells located on the thymus FRQ: Consider the nonspecific immune responses in plants and animals. a.There has been recent research on the similarities between the nonspecific immune responses of plants and animals. Using the graphs above give at least 3 similarities between the two. b.Using your previous knowledge about the nonspecific immune responses in humans to draw and label the inflammatory response that occurs when the bacteria enters c.For Part c, describe what you have drawn in part b Use the purple side

Answer Key! MC Question: Which of the following would be classified as the best form of the first line of nonspecific immune response? a.The natural killer cells perforate the cells by releasing the protein perforin b.Using the polio vaccine to help combat against the loss of motor function c.The stomach acid pH eating away bacteria that enters that region of the body d.The T cells attacking the abnormal growth of cells located on the thymus Explanation: The correct answer is C because the nonspecific immune immune system is composed of elements like the skin, coughing, sweat, and even the unfavorable pHs (stomach acid). This is because they eliminate the invading pathogen as the first line of defense for the immune system, but do not remember this pathogen for the next time that it invades the body. FRQ: Consider the nonspecific immune responses in plants and animals. a.There has been recent research on the similarities and differences between the nonspecific immune responses of plants and animals. Using the images above and previous knowledge give at least 3 similarities or differences between the two. b.Using your previous knowledge about the nonspecific immune responses in humans to draw and label the inflammatory response that occurs when bacteria enters c.For part c, describe what you have drawn in part b. a.Like animals, plants have acquired the ability to recognize invariant pathogen-associated molecular patterns that are characteristic of microbial organisms but which are not found in potential host plants. (both recognize self from nonself) They both contain macrophages, but in the human system we contain the T and B cells that help with memory. The plants do not have a circulating immune system, so each plant cell individually responds to the invader. c. The inflammatory response is the response that occurs in the body when there is damage to the tissues. This is a local and non-specific response. The mast cells release chemical signals like histamines and the capillaries dilate to become more permeable. This will cause the delivery of macrophages, RBCs, platelets, and clotting factors to the localized area. These agents will fight the pathogens and begin to form a clot. This area will also increase in temperature to stimulate phagocytosis, decrease bacterial growth, and speed up the repairs of tissues.

LO 3.8: The student can describe the events that occur in the cell cycle. SP 1.2: In eukaryotes, heritable information is passed to the next generation via processes that include the cell cycle and mitosis or meiosis plus fertilization. Explanation: In a dividing cell, the mitotic (M) phase alternates with interphase, a growth period which accounts for about 90% of the cycle. The first part of interphase, called G1 (first gap), is followed by the S phase (synthesis), while the last part is called G2 (second gap). In the mitotic (M) phase, mitosis occurs and is broken down into stages of prophase, prometaphase, metaphase, anaphase and telophase. Then, cytokinesis occurs overlapping the later stages of mitosis. This process occures in all cells that are not the sperm and egg. Interphase: G1, S, G2 G1: cell grows S:continues to grow as it copies its chromosomes G2: grows more as it, nuclear envelope bounds nucleus Mitotic Phase: prophase, prometaphase, metaphase, anaphase, telophase, cytokinesis Prophase: chromatin condenses, two identical sister chromatids join together, mitotic spindle begins to form, centromeres begin to move away from eachother Prometaphase: microtubules extend from each centromere towards middle of cell, kinetochore appears and some microtubules attach Metaphase: longest stage, centrosomes at opposite ends, kinectochores of sister chromatids attach to microtubules Anaphase: shortest stage, sister chromatids separate and begin moving towards opposite sides, cell elongates Telophase: two daughter nuclei form, chromosomes less condensed, nuclear envelopes begin to form Cytokinesis: division of cell resulting in two daughter cells http://www.citruscollege.edu/lc/archive/biology/Pages/Chapter08 -Rabitoy.aspx MC: How is the anaphase stage of the mitotic cycle defined? A. DNA begins to replicate B. Centrosomes move to opposite ends of the poles C. Daughter chromosomes move towards opposite ends of the cell D. Two daughter nuclei begin to form in the cell FRQ: Every stage of the cell cycle is essential for proper development. A. List the stages of the cell cycle. B. Describe the longest and shortest stage of the cell cycle. C. In what stage is an error most likely to occur and what is a potential outcome of that error? D. Describe the importance of each stage of interphase.

MC: How is the anaphase stage of the mitotic cycle defined? A. DNA begins to replicate B. Centrosomes move to opposite ends of the poles C. Daughter chromosomes move towards opposite ends of the cell D. Two daughter nuclei begin to form in the cell Explanation: During the anaphase stage, which is the shortest, the two sister chromatids of each pair begin to pull apart. Each chromatid then becomes a full fledged chromosome. The two chromosomes begin moving towards opposite ends of the cell, centromere first, as their kinetochore microtubules shorten pulling them to the ends. FRQ: Every stage of the cell cycle is essential to proper development. A.List the stages of the cell cycle. B.Describe the shortest and longest stage of the cell cycle. C.In what stage is an error most likely to occur and what is a potential outcome of that error? D.Describe the importance of each stage in interphase A.Interphase, which consists of the G1, S and G2 stage. Followed by mitosis which consists of prophase, prometaphase, metaphase, anaphase, telophase and cytokinesis. B.The shortest stage of the cell cycle is anaphase which is where sister chromatids separate and move towards opposite ends of the cell. The longest stage is metaphase which is when kinectochores attach to microtubules. C.The most common stage errors are made in is the metaphase stage when the chromosomes align in the middle of the cell. If the chromosomes do not pair properly then they will not separate properly during anaphase. This resulting in one daughter cell not having enough or having too many chromosomes. Not enough could be fatal to the cell while having too many would lead to an increase in expression of genes and if they promote growth the cell would grow uncontrollably, leading to cancer. D.The importance of the G1 stage is the growth and young maturation occurs and the protein and RNA synthesis resumes. The importance of the S phase is that the replication of cellular DNA occurs to get passed and equally distributed to the daughter cells. The importance of the G2 phase is that proof reading and repair among the new DNA that is synthesized before the cell goes through the mitotic cycle.

Explanation: The nervous system detects and responds to signals through neurons. As seen in the figure, sensory neurons receive an initial stimulus from a sense organ such as the eyes and ears, or from another neuron. After receiving a stimulus, the sensory neurons send information to the interneurons residing within the spinal cord and brain. The information is then transferred directly to a motor neuron or the brain for processing. Neurons receive incoming messages through their dendrites, sensory cytoplasmic extensions that receive information from other cells and carry the electrical signal to the cell body. Axons transmit an impulse from the cell body outward towards another cell. Before experiencing an electrical impulse, the cell is at resting potential (approximately -70 mV). However, once the axon becomes depolarized, potassium ions flood out of the cell while sodium ions flood in. If this impulse reaches the threshold (-55 mv), the neuron reaches action potential and the impulse is fired. It then undergoes a refractory period to repolarize. Action potential generates multiple action potentials within other cells moving in one direction. After reaching the end of the axon, it crosses a synapse chemically where it is received by post synaptic receptors and the cycle restarts if the stimulus is strong enough. The nervous system consists of central and peripheral components. The central nervous system (CNS) consists of the brain and spinal cord while the peripheral nervous system (PNS) consists of all nerves outside the CNS. The PNS is divided into sensory and motor components. Sensory conveys information from sensory receptors or nerve endings while motor consists of the somatic system and the autonomic system. The somatic system controls voluntary muscles while the autonomic controls involuntary muscles. The autonomic can be broken down into sympathetic and parasympathetic. Sympathetic controls fight or flight response, increases heart rate, the liver converts glycogen to glucose, the bronchi of lungs dilate and increases gas exchange, and adrenalin raises blood glucose levels. The parasympathetic nervous system opposes the sympathetic system, calming the body, decreasing heart and breathing rate and enhances digestion. LO 3.43: The student is able to construct an explanation, based on scientific theories and models, about how the nervous system detect external and internal signals, transmit and integrate information, and produce responses SP 6.2:The student can construct explanations of phenomena based on evidence produced through scientific practices. SP 7.1: The student can connect phenomena and models across spatial and temporal scales. MC Question: Which sequence of events is correct regarding a complex reflex arc? 1.A sensory neuron transmits an impulse to the spinal cord 2.A motor neuron stimulates muscles or glands to perform contraction or secrete enzymes 3.A sensory neuron detects a stimulus 4.Interneurons process impulse A)1,4,3,2 B)3,2,4,1 C)4,1,3,2 D)3,1,4,2 FRQ: Consider the transmission of nerve impulses a. For each, describe its purpose in transmitting signals throughout a neuron i.Dendrites ii.Axon hillock iii.synapse b. What factors contribute to the generating action potential? c. Consider the role of the sodium- potassium pump. If the pump was not functioning, predict what would occur and explain why. d. Action potential can only travel in one direction. Why is this the case?

MC Question: Which sequence of events is correct regarding a complex reflex arc? 1.A sensory neuron transmits an impulse to the spinal cord 2.A motor neuron stimulates muscles or glands to perform contraction or secrete enzymes 3.A sensory neuron detects a stimulus 4.Interneurons process impulse A)1,4,3,2 B)3,2,4,1 C)4,1,3,2 D)3,1,4,2 Answer Key Explanation: A complex reflex arc consists of three neurons, sensory, motor, and interneurons. Once the sensory neuron detects a stimulus from an outside source, it transmits an impulse to the interneuron in the spinal cord, which sends one impulse to the brain for processing and also one to the motor neuron to effect change immediately (at the muscle.) This is the type of response that jerks your hand away after touching a hot stove before your brain processes what has occurred. FRQ: Consider the transmission of nerve impulses a. For each, describe its purpose in transmitting signals throughout a neuron i.Dendrites ii.Axon hillock iii.synapse b. What factors contribute to the generating action potential? c. Consider the role of the sodium-potassium pump. If the pump was not functioning, predict what would occur and explain why. d. Action potential can only travel in one direction. Why is this the case? a.Dendrites- branched cytoplasmic extensions from a neuron that bring signals to cell body Axon hillock- cell body region where impulse is generated and axon begins; determines overall charge… if threshold is met then action potential is fired Synapse- junction between neurons or neuron and muscle or gland; transfers electric activity from one cell to the other b. Action potential can only be generated in the axon of a neuron. Neurons have gated-ion channels that open or close in response to a stimuli. Sodium ion-gated channels open and sodium flows into the cytoplasm, somewhat depolarizing the membrane. In response, potassium channels open and potassium ions flood out of the cell. The rapid movement of ions cause a wave of depolarization reversing the polarity of the membrane. If the membrane potential reaches -55 mV, action potential occurs. c. The sodium-potassium pump restores the membrane to its original polarized condition by pumping sodium and potassium ions back to their original position. If the sodium-potassium pump was not functioning, repolarization would not occur therefore inhibiting another action potential. In addition, the cell would not gain equilibrium, as an excess of sodium will remain inside the cell. The increase in positively charged ions would cause water to enter the cell. The increase in osmotic pressure would allow so much water into the cell that the cell will lyse (rupture). d. An action potential is generated as Na+ flows inward across the membrane at one location. The depolarization of the action potential spreads to the neighboring region of the membrane, re-initiating the action potential there. To the left of the region, the membrane is repolarizing as K+ flows outward. The depolarization-repolarization process is repeated in the next region of the membrane. In this way, local currents of ions across the plasma membrane cause the action potential to be propagated along the length of the axon from left to right.

LO 1.9: The student is able to evaluate evidence provided by data from many scientific disciplines that support biological evolution. SP 5.3: The Student can evaluate the evidence provided by data sets in relation to a particular scientific question. Explanation: Evolution can be defined as gradual heritable change over time. A phrase summarizing evolution is “Descent with Modification”. All organisms are related through descent from a common ancestor who lived many years ago. The descendants of that ancestral organism have found their way to many locations and habitats, obtaining adaptations (modifications) to support them in their various ways of life. The key mechanism to evolution is the process of natural selection. Natural selection is differential reproductive success, as this occurs between environmental interactions by variability in populations. The adaptations by these populations to their environments is the product of natural selection, and the basis of evolution. Evidence supporting evolution can be found in many scientific disciplines. Highly complex organisms such as Lamprey’s sharing 14% of Amino Acids identical in a Human Hemoglobin Peptide, obviously a very different species than a Lamprey. The comparison of these Amino Acids, the building blocks for proteins, illustrate that two very different species still have the basic and required components to their DNA remain similar in some fashion, showing that both were derived from a common ancestor. Figure 22.6 – Comparison of a protein found in diverse vertebrates A species of lizard lives on a rocky island. 70% of the lizards have brown skin (AA allele), 20% have brown with green spots (Aa allele), and 10% have green skin (aa allele). A) How has natural selection likely effected these lizards. B) Since having green spots does not have much physical benefit, what is the benefit of having it in the Aa allele? C) A hurricane sweeps through the island, leaving a small amount of random survivors. Identify what cause of microevolution was behind this situation, provide evidence to support. Multiple Choice Free Response On an island, two species of bird, one with webbed feet and one without, live together without competition. Heavy rain always flooded the island until an extended drought hit. Which answer best describes the effect of the drought on the species as shown by the graph? A) The non-webbed species reproduced more frequently, thus growing their population. B) With the floods down, the non-webbed species was able to move around without drowning, thus increasing their survival rate. C) The webbed population heavily decreased due to the growth of the non-webbed population. D) As soon as the floods decreased, the Non-webbed species saw a rapid increase in survival rate.

Answer Key Multiple Choice A) Incorrect. Rate of reproduction has no correlation to rate of survival. Just because you produce more children, does not make any of them more likely to survive. B) Correct. Previously on the island, floods created bodies of water throughout the island. The non-webbed species could not swim in these waters as well as the webbed species, meaning there was a high likelihood of drowning for the non- webbed species. Their non-webbed feet were selected against, and could only be selected for once water and floods were not an issue. C) Incorrect. It was previously stated that the two species do not compete for the same resources, meaning they can survive together, no matter the respective population size. D) Incorrect. Natural Selection takes time to occur. The drought took many years to complete, so flood levels were not entirely at zero from day one. Generations of non-webbed species have to continue to be born for the survival rate to increase, as each new generation sees lower flood levels, and thus has a higher likelihood of survival. Free Response A) Natural selection has likely effected these lizards by selecting for the brown skin, which acts as camouflage against the rocky habitat. Lizards with the green skin and green-dotted skin are easier to see against the dark colored rock, making them more vulnerable to predators. The brown lizards could survive because their predators had a much harder time seeing them. B) The Aa allele is beneficial due to its contribution towards higher genetic variation. At some point down the line, the lizard’s environment may shift and select for the green-spotted skin rather than the two solid colors. Having this allele available could be the key to the survival of the lizard species in the future. C) Genetic Drift was the cause of microevolution in this situation. Genetic Drift is when a gene pool changes to a small population due to chance. In this depicted situation, the lizard population was greatly reduced by the lethal hurricane, leaving few survivors. This holds up the small population requirement for genetic drift. The lizards that did survive were random, they could have simply been lucky to be in the right place at the right time, their skin color had nothing to do with their survival in the face of the storm. This random survival can also be called “due to chance”, which directly is the definition of genetic drift.

LO 4.27 The student is able to make scientific claims and predictions about how species diversity within an ecosystem influences ecosystem stability SP 6.4 The student can make claims and predictions about natural phenomena based on scientific theories and models Explanation: All the biological systems are composed of parts that cooperate with each other. These biological systems that begin with the molecular level and end with the ecosystem level display properties of bio complexity and diversity. The biological systems with greater complexity and diversity demonstrate an increased capacity to respond to changes in the ecosystem. The community structures can change as the environmental conditions change. The communities are a combination of diverse species that interacts with each other in different ways either, negatively or positively. As environmental conditions change the structure of the community changes both physically and biologically, resulting in a variety of patterns in the community. For example in the diagram to the right, community 1 is more diverse because there is an equal variety of trees that helps stabilize the ecosystem because it gives a numerous amount of resources for the surrounding species whereas community 2 has an overpowering amount of one tree which decreases the amount of species that rely on the other three trees. Interactions between populations within communities also lead to ecosystem stability. Ecosystems include producers, consumers and decomposers. Community ecology seeks to understand how species in these trophic levels are distributed in nature and how they are influenced by their abiotic environment and their biotic factors. Examples of abiotic favors would be weather, climate, environmental disasters, the depth and flow of a stream etc. Examples of biotic factors would be resource limitation, health, predation and waste accumulation. These abiotic and biotic disturbances can follow a pattern such as a wildfire or it can be random and unpredictable such as the founder effect. Wildfires can help stabilize an ecosystem because they help replenish the ecosystem so it can grow with recycled nutrients, increased food sources, and less debris. MC Questions: What does NOT contribute to the stability of an ecosystem? A)Abiotic Factors B)Biotic Factors C) Keystone Species D)Nonnative Species FRQ: Consider a biologically diverse ecosystem on the coastline of North Carolina. The ambrosia beetle is native to Asia and was first noticed on peach trees in Charleston in 1974. There was a wide spread of these beetles in the costal plain and piedmont of South Carolina. They bore into stems and can kill many fruit, nuts and ornamental trees, including peach, pecan and persimmon. a.How can the introduction of the Ambrosia Beetle disrupt the stability of the ecosystem. b. Give an example of an abiotic and biotic factor that can help stabilize the ecosystem and how. http://slideplayer.com/slide/9432033/

MC Questions: What does NOT contribute to the stability of an ecosystem? A.Abiotic Factors B.Biotic Factors C. Keystone Species D.Nonnative Species Explanation: Abiotic factors, such as wildfires, weather and temperature help contribute to the stability of the ecosystem. Wildfires can help stabilize an ecosystem because they help replenish the ecosystem so it can grow with recycled nutrients, increased food sources, and less debris. The species that can survive through the harsh conditions are the ones that natural selection chose to have their genes passed on to the next generation. Biotic factors, such limited resources and competition also help stabilize the ecosystem. Species that have a specific or picky diet cannot survive in a low diversity and high competitive ecosystems. This helps keep the circle of life on circulation. Keystone species are a necessity for ecosystem stability, For example sharks and bees. Sharks are the top of the food chain in the ocean. They help keep the food chain in tacked and keep fish from over populating the oceans. Bees are basically responsible for spring. They are the pollinators that help fertilize different plants and help seed dispersal. Without keystone species, new plants and animals (Nonnative Species) could also come into the habitat and push out the native species. Nonnative species destroy habitats and causes a decline of natives species because of the competition for the same limited resources. The nonnative species brings in diseases and parasites that are nonnative to the new environment. Answer Key FRQ: Consider a biologically diverse ecosystem on the coastline of South Carolina. The ambrosia beetle is native to Asia and was first noticed on peach trees in Charleston in 1974. There was a wide spread of these beetles in the costal plain and piedmont of South Carolina. They bore into stems and can kill many fruit, nuts and ornamental trees, including peach, pecan and persimmon. A.How can the introduction of the Ambrosia Beetle disrupt the stability of the ecosystem. B.Give an example of an abiotic and biotic factor that can help stabilize the ecosystem and how. A.The ambrosia beetles are nonnative species in the South Carolina costal plain. These beetles have bored into important fruits, nuts and ornamental trees that disrupts the stability of the ecosystem. It disrupts the stability by killing fruits, nuts and trees that are vital to the survival of the organisms that are native to the South Carolina costal plain. Since the limited resources are being killed, it is causing the native organisms to move out of their natural habitat causing the ecosystem to become unstable. B. An example of an abiotic factor would be wildfires. Wildfires can help stabilize an ecosystem because they help replenish the ecosystem so it can grow with recycled nutrients, increased food sources, and less debris. An example of a biotic factor would be competition. Competition helps eliminate the “weak” species that aren’t willing to fight for the limited resources or they just give up and move on, therefore not allowing there genes to be reproduced in the next generation due to natural selection.

LO 2.19: The student is able to make predictions about how positive feedback mechanisms amplify activities and processes in organism based on scientific theories and models. SP 6.4: The student can make claims and predictions about natural phenomena based on scientific theories and models. Explanation: Positive feedback is a mechanism that pushes an organism’s body further out of a homeostatic state when the external surroundings change. This pushes the levels away from the set point. Sometimes it is necessary for life. Positive feedback the output from the control center enhances or amplifies the original stimulus. The variable starting the reaction moves the away from the initial set point when amplified. Amplification takes place when the stimulus is further activated, which changes the system. Positive feedback will continue to push variable until an external forces terminates it. An example of this is uterine contraction during childbirth (e.g. Figure 1). When the baby is pushing against the mother’s cervix a signal is sent. Nerves in a woman’s cervix tell the hypothalamus to release oxytocin. The posterior pituitary gland secretes oxytocin into the bloodstream. Blood vessels carry the hormone to the tissues of the uterus. Oxytocin causes the uterus to contract more and stronger. As a baby descends, more oxytocin is until the cervix is fully dilated, at 10 cm, and the baby is expelled. The expulsion of the newborn baby is what halts the stretch of the cervix, which in turn terminates the release of oxytocin. Other examples of positive feedback in humans are blood clotting and lactation. An example in plants is the ripening of a fruit by the plant hormone, ethylene. The stimulus is the plant releasing ethylene; the response is the increased and continued production of ethylene. A ripening fruit releases ethylene, the existence of ripened tissues increases the amount of ethylene being released. Nearby fruit release ethylene additionally to ripen, causing increased amount of ethylene being emitted. Figure 1: http://cnx.org/contents/8Q_5pQQo@4/Homeosta sis MC Question: What happens if the oxytocin stops being released during childbirth? a)Birthing stills happens, but is slower; the baby continues to push on the birth canal until is stretched enough for it to go through and the baby will still be in its amniotic sac. b)Child birthing stops and the baby goes back up in to the uterus. c)Child birthing stops, but the baby will stay in the same place when the oxytocin stopped being released. d)Birthing continues as normal, because once the cervix starts to open it can’t stop. FRQ: Consider how ethylene used in a plant and the concepts of fruit ripening. a)Why does a fruit ripen faster when put in a paper bag? b)Positive feedback can be good, there are some setbacks to it. Not including fruit ripening, what are some other results of the production of ethylene? c)How has ethylene helped the first plants survive and reproduce during natural selection? d)What companies and businesses are helped by the natural production of ethylene and how?

Answer Key: MC Question: What happens if the oxytocin stops being released during childbirth? a)Birthing stills happens, but is slower; the baby continues to push on the birth canal until is stretched enough for it to go through and the baby will still be in its amniotic sac. b)Child birthing stops and the baby goes back up in to the uterus. c)Child birthing stops, but the baby will stay in the same place when the oxytocin stopped being released. d) Birthing continues as normal, because once the cervix starts to open it can’t stop. Explanation: Without oxytocin the contractions of the uterus will stop. This will stop the dilation of the cervix making it remain partially closed. The baby then can’t move further down the mother’s cervix. The infant will not travel back up to it’s original position before birth has started. This is because once labor, contractions of the uterus, has started the baby can’t moved back into the womb fully. FRQ: Consider how positive feedback works and examples. a)Why does a fruit ripen faster when put in a paper bag? b)Explain the familiar saying, “One bad apple spoils the whole” with using your knowledge about positive feedback. c)What is the variable that is being pushed away from its set point during uterine contractions? d)What would happen if the baby doesn’t push against the uterine wall? a)The ethylene that is released by the fruit is trapped by the paper bag. This concentrates the levels of ethylene in the paper bag. Through positive feedback, the presence of big amounts of ethylene in the paper bag will cause rate of ethylene being emitted to be increased. b)Fruits, including apples, produce ethylene in their aging tissues. If many apples are stored in one area, the spoiled apple that is producing ethylene will cause the others to produce ethylene also. The high concentration of the ethylene, more apple will become ripen and then rotten. The more ripe an apple is the more ethylene is produced. c)The variable that is being pushed away from its set point is oxytocin. During birth oxytocin levels increase because of the baby pushing on the cervix. As birthing continues, oxytocin levels will rise, until the baby is born. d)There is no stimulus, thus there won’t be an output to enhance the stimulus. The posterior pituitary gland will not release oxytocin into the bloodstream. Contractions of the uterus will not commence.

LO 1.11: The student is able to design a plan to answer scientific questions regarding how organisms have changed overtime using information from morphology, biochemistry and geology. SP 4.2: The student can design a plan for collecting data to answer a particular scientific question. Explanation: Charles Darwin was an English naturalist who came up with a theory of evolution which was that everything in life descended from a common ancestor. Morphological homologies prove Darwin’s theory. They show different structures that have features shared by a common ancestor. Questions regarding his theory can also be proved by facts dealing with evidence from fossils. Fossils are so critical to providing evidence of evolution because they show the changing overtime of similar organisms from a common ancestor. Fossils are facts, they cannot be tempered with; therefore, everything about them has a scientific cause to it. Biochemical similarities in DNA protein and nucleotide sequences have a factual benefit in answering questions by showing linkages in organisms. To test this you could look at fossils from different time periods. If you look at fossils from one billion years ago you will see that the organisms were single celled. 550 million years ago fish without jawbones lives. Fossils 400 million years ago showed fish with jawbones. 350 million years ago is when amphibians came about. You can keep going down the timeline all the way until now, when there will be linkages from humans to fossils a long time ago. Every organism will have a linkage to a common ancestor. MC Question: Why do certain species survive on Earth and other species go extinct? A.The ones that survive are lucky and the ones that do not survive are unlucky. B.The species that go extinct do not have as quick, or quick enough, reproductive rates and cannot reproduce as fast. They go extinct because predators kill them before many of them can even reproduce. C.Not all species can handle environmental changes. Natural selection will remove the organisms that cannot adapt. D.Many species are overhunted or overgrazed and it is the human populations fault that these organisms are going extinct. FRQ: The peppered moth was once a light colored moth from England before the Industrial Revolution. By 1895, 95% of the peppered moth population was a dark color. During the early years of the Industrial Revolution, coal was burned producing dark soot. A.Describe why the light color coat changed to a dark color coat. B.England cleaned up their air in the late 1900’s, making trees become light again. Dark moths then became rare. Why? C.What genetic change could have occurred in the moths and what would it have done? D.The environmental change for these moths was the pollution in the air, making the landscape darker. Which of the five conditions of Hardy Weinberg equilibrium did this effect?

Answer Key: MC Question: Why do certain species survive on Earth and other species go extinct? A.The ones that survive are lucky and the ones that do not survive are unlucky. B.The species that go extinct do not have as quick, or quick enough, reproductive rates and cannot reproduce as fast. They go extinct because predators kill them before many of them can even reproduce. C.Not all species can handle environmental changes. Natural selection will remove the organisms that cannot adapt. D.Many species are overhunted or overgrazed and it is the human populations fault that these organisms are going extinct. MC Question answer: C. Not all species can handle environmental changes. Natural selection will remove the organisms that cannot adapt. Explanation: The species that is the most fit will survive to reproduce, passing on the traits to successfully survive in that environment. The ones that are not a good fit for that particular environment will be selected against. Natural selection occurs and removes the weakest out of the environment so that they do not produce offspring, which would not be likely to survive in that environment. FRQ: The peppered moth was once a light colored moth from England before the Industrial Revolution. By 1895, 95% of the peppered moth population was a dark color. During the early years of the Industrial Revolution, coal was burned producing dark soot. A.Describe why the light color coat changed to a dark color coat. B.England cleaned up their air in the late 1900’s, making trees become light again. Dark moths then became rare. Why? C.What genetic change could have occurred in the moths and what would it have done? D.The environmental change for these moths was the pollution in the air, making the landscape darker. Which of the five conditions of Hardy Weinberg equilibrium did this effect? FRQ answers: A. The peppered moths coat color changed from light to dark to better camouflage itself. The coal and soot gave off so much pollution that the landscapes darkened and the tree bark did too. The lighter moths were not as well camouflaged against the dark bark as the dark ones were. Natural selection occurred and made the light moths more likely to be eaten by birds since they stood out more against trees than the dark ones did. B. The complete opposite of A. The dark moths now stood out against the light bark on the trees. They are now more likely to be eaten and therefore, selected against. C. A mutation in the DNA could have caused a change in the nucleotide or amino acid sequence and caused the change in the phenotype of the moths. D. No natural selection.

LO 2.29: The student can create representations and models to describe immune responses. SP 1.1: The student can create representations and models of natural or man-made phenomena and systems in the domain. SP 1.2: The student can describe representations and models of natural or man-made phenomena and systems in the domain. Explanation: The immune system has three main lines of defense that are able to respond to new threats as soon as they appear. The first line of nonspecific defense is a barrier that prevents pathogens from entering the body and this includes, the skin, mucous membranes, and stomach acid.. The second line of nonspecific defense is meant to limit the spread of invaders in advance of specific immune responses, and this includes inflammatory responses, phagocytes, complements, and interferon's. The phagocytic white blood cells are attracted by chemical signals that are released by damaged cells. They ingest pathogens and digest in lysosomes and the types include neutrophils, macrophages and natural killer cells. Neutrophils are the most abundant white blood cell, macrophages are the “big eaters,” and the natural killer cells destroy virus-infected cells and cancer cells. The adaptive third line of defense relies on B lymphocytes and T lymphocytes, which come from stem cells in bone marrow. The adaptive immune response is a specific response and involves three phases: recognition, activation phase, and effector phase. T lymphocytes fight pathogens in the cell-mediated immune response, and B lymphocytes provide adaptive immunity through the humoral immune response. MC Question: What is the correct order of the three lines of defense? 1. Non-specific barriers that have broad, external defense, like the skin and mucous membranes. 2. The true immune system that is specific and has acquired immunity, like lymphocytes and antibodies. 3.Non-specific patrols that have broad, internal defense, like leukocytes. a) 1,2,3 b) 1,3,2 c) 3,2,1 d) 2,1,3 https://health4life83.files.wordpress.com/2015/09 /screen-shot-2015-09-29-at-3-17-49-pm.png FRQ: Consider innate immunity and adaptive immunity. a.Name three differences between innate immunity and adaptive immunity. b.Innate immunity is our first defense against invaders. Name the major components of innate immunity and describe them in detail. c.The adaptive immune response is mediated by immune cells known as lymphocytes. Name the two types of lymphocytes and describe them in detail.

MC Question: What is the correct order of the three lines of defense? 1. Non-specific barriers that have broad, external defense, like the skin and mucous membranes. 2. The true immune system that is specific and has acquired immunity, like lymphocytes and antibodies. 3.Non-specific patrols that have broad, internal defense, like leukocytes. a) 1,2,3 c) 3,2,1 b) 1,3,2 d) 2,1,3 Explanation for MC: The first line of defense is the non-specific external defense. It has barriers, traps, elimination, unfavorable pH’s, and lysosome enzymes. The second line of defense is the non-specific patrolling cells. It has patrolling cells and proteins that attack pathogens, but they do not “remember” for the next time a pathogen tries to attack. The third line of defense is the acquired active immunity. This line has a specific defense with a memory which are the lymphocytes and antibodies, and they respond to antigens. FRQ: Consider innate immunity and adaptive immunity. a.Name three differences between innate immunity and adaptive immunity. b.Innate immunity is our first defense against invaders. Name the major components of innate immunity and describe them in detail. c.The adaptive immune response is mediated by immune cells known as lymphocytes. Name the two types of lymphocytes and describe them in detail. Explanation for FRQ: a.Innate immunity is non-specific and the adaptive immunity is specific to antigens. Innate immunity has an immediate response and adaptive immunity has lag time from exposure to response. Innate immunity has no immunological memory, and adaptive immunity has immunological memory after exposure. b.The epithelial and mucosal linings of our respiratory and GI tracts, as well as our skin are major components of the innate immune system. These act as physical and chemical barriers against pathogens. Cells known as macrophages also play a large role in innate immunity. Macrophages recognize bacterial or viral components such as lipopolysaccharide (LPS) or double-stranded RNA (dsRNA), via special receptors known as Toll-like receptors (TLRs). TLR activation cause macrophages to secrete cytokines (small molecules involved in cell signaling and attraction), as well as to phagocytose the infected cells. The innate immune system is required to activate our adaptive immune system. c.These are B and T cells. B cells secrete antibodies, highly specific protein molecules that bind to a specific pathogen. These antibodies bind specific parts of pathogens known as antigens - either presented extracellularly on infected cells or free- floating in the body. Antibody binding attracts mechanisms that will then attack and destroy the infected cell or pathogen. Some of these B cells become memory cells, which help the body “remember” the disease and prevent re-infection. T cells can either be helper T cells or cytotoxic T cells, and bind pathogens via the T-cell receptor (TCR), which senses specific protein sequences. Helper T cells activate B cells, attract macrophages, and secrete cytokines. Cytotoxic T cells create pores in infected cells through which they introduce chemicals that trigger apoptosis, thus actively killing the cell. ANSWER KEY

LO 3.48: The student is able to create a visual representation to describe how nervous systems detect external and internal signals. SP 1.1: The student can create representations and models of natural or man-made phenomena and systems in the domain. Explanation: Signals are sent through the nervous system using specialized cells called neurons. The signal travels as an action potential and enters the dendrites of the neuron. The AP travels through the cell body and then down to the end of the axon. Neurotransmitters leave the presynaptic cell through exocytosis when the AP reaches the end of the axon. The neurotransmitters activate ligand gated ion channels on the dendrites of the postsynaptic cell, creating a new action potential. This process happens millions of times per second, and is the basis for all neurological activity. A receptor cell detects a stimulus (such as touch, hearing, taste, sight, smell, etc.) and creates an action potential. This AP is transmitted to a sensory neuron. The sensory neuron sends the signal to interneurons to in either the brain and spinal cord. The interneurons process the input, and send a signal down motor neurons to make an appropriate response. The interneurons of the brain and spinal cord make up the Central nervous system, and other sensory and motor neurons make up the peripheral nervous system. FRQ: Action potentials are created when neurons become depolarized. A)Sodium ions enter a neuron and depolarize it by +20 mV. Does the neuron create an action potential? B)Explain the process that occurs when an action potential reaches the end of the axon in a presynaptic cell. C)Explain how neurotransmitters and ions interact with a postsynaptic cell to produce an action potential. MC Question: The withdrawal reflex is a reflex arc that protects the body from a harmful stimulus, such as a hot object. How would the removal of sensory neurons from this reflex arc affect motor neurons? A) The action potential will reach the end of the motor neuron faster because there are fewer neurons for the AP to travel through. B) The motor neurons will not be stimulated because no action potential will be created by the sensory neurons. C) The removal of sensory neurons will not affect this reflex arc because motor neurons can send the D) The motor neuron is not affected because the action potential originates in the central nervous system. Nick Miller

Answer Key MC Question: The withdrawal reflex is a reflex arc that protects the body from a harmful stimulus, such as a hot object. How would the removal of sensory neurons from this reflex arc affect motor neurons? A) The action potential will reach the end of the motor neuron faster because there are fewer neurons for the AP to travel through. B) The motor neurons will not be stimulated because no action potential will be created by the sensory neurons. C) The removal of sensory neurons will not affect this reflex arc because motor neurons can send the D) The motor neuron is not affected because the action potential originates in the central nervous system. Explanation: Neurons create action potentials that travel in only one direction. In the reflex arc, the AP must travel from the sensory neuron to the interneurons, in order to be passed along the motor neuron. The removal of the sensory neuron will prevent any signal from reaching the interneurons and motor neurons. This leads to no response because the motor neuron did not receive any signal. FRQ: Action potentials are created when neurons become depolarized. A)Sodium ions enter a neuron and depolarize it by +20 mV. Does the neuron create an action potential? B)Explain the process that occurs when an action potential reaches the end of the axon in a presynaptic cell. C)Explain how neurotransmitters and ions interact with a postsynaptic cell to produce an action potential. A)-70mV+20mV=-50mV Because the threshold potential for most neurons is -55mV, an action potential will be created. B)When an action potential reaches the end of the axon, it activates voltage gated ion channels in the plasma membrane. The channels allow for Ca 2+ ions to enter the cell. Vesicles containing neurotransmitters fuse with the plasma membrane due to the high concentrations of Ca 2+ ions. The vesicles release the neurotransmitters through exocytosis into the synapse between the synapses. There the neurotransmitters can bind with receptors on the postsynaptic cell. C)Neurotransmitters bind with ligand gated ion channels on the plasma membrane of the postsynaptic cell. The channels allow for Na + ions to enter the cell and raise its membrane potential. Neurons have a resting potential of -70mV. When enough Na + ios enter to raise the cell’s charge to -55mV, then an action potential is created. Even more sodium channels open, quickly depolarizing the cell up to +50mv. At this point, sodium channels close and potassium channels open to repolarize the neuron. The cell will temporarily become hyperpolarized, because the influx of potassium ions bring the membrane potential to less that -70mV. The K + ion channels close and sodium potassium pumps move the ions across the cell membrane to bring the neuron back to its -70mV resting potential.

Explanation: The variety of populations fluctuates based on favorable phenotypes. Competition for limited resources demands supreme traits. Those organisms with the best traits have the greatest chance of reproductive success. Therefore, the most beneficial traits are passed down through generations, and soon the entire population of organisms adopts the favorable traits, and those without the trait die off. Mathematically, one can apply methods to phenotypic frequencies to illustrate the future of populations. FRQs: During the Industrial Revolution, bark color darkened and along with it the moth populations grew darker. Use the data in the graph and your understanding of populations to answer the following questions. a.Calculate the mean rate of population growth from 0 to 5 generations for dark colored moths. Include proper units. b. Evaluate the mean rate of population growth from 0 to 5 generations for light colored moths. Include proper units. c.Explain why the growth rates for each light moths and dark moths are positive or negative. d.As the trees continue to darken as a result of the Industrial Revolution, according to the data, what will likely occur to the moth population as a whole? What type of selection occurs? d.Hypothetically, if the trees became half light and half dark, what could occur in the light and dark moth populations, regarding stabilizing selection. LO 1.3: The student is able to apply mathematical methods to data from a real or simulated population to predict what will happen to the population in the future. SP: The student can use mathematics to predict the future of populations. MC Question: 1000 tiny canines rush onto an island after a pet transport vessel crashes into an isolated Hawaiian land mass. 250 of the dogs have brown fur, 250 gray, 250 black, and 250 white. The island is carpeted by a vast quantity of black sand. What type of selection will occur, and what are the most likely figures of this population after 100 years of no significant environmental or human interference. A.Directional Selection; 975 black, 25 brown B.Directional Selection: 900 brown, 100 black C.Stabilizing Selection: 1000 with gray/white fur D.Disruptive Selection: 500 black, 500 white E.Stabilizing selection: 1000 black/white http://schoolworkhelper.net/industrial-melanism-and-the-peppered-moth-lab-answers /

Answer Key: MC Question MC Question: 1000 tiny canines rush onto an island after a pet transport vessel crashes into an isolated Hawaiian land mass. 250 of the dogs have brown fur, 250 gray, 250 black, and 250 white. The island is carpeted by a vast quantity of black sand. What type of selection will occur, and what are the most likely figures of this population after 100 years of no significant environmental or human interference. A.Directional Selection; 975 black, 25 brown B.Directional Selection: 900 brown, 100 black C.Stabilizing Selection: 1000 with gray/white fur D.Disruptive Selection: 500 black, 500 white E.Stabilizing selection: 1000 black/white Explanation: The black fur on the black dogs acts as camouflage from various predators. The black fur blends in with the black sand. Therefore, more black canines will be able to survive and reproduce over time and produce the highest population numbers. This directional selection marks a favoring of one extreme, dark fur color on the island. The favorable trait is simply dark fur, preferably black. FRQs: During the Industrial Revolution, bark color darkened and along with it the moth populations grew darker. Use the data in the graph and your understanding of populations to answer the following questions. a.Calculate the mean rate of population growth from 0 to 5 generations for dark colored moths and light moths. b. Explain why the growth rates are positive or negative. c.If trees continue to darken, according to the data, what will likely occur in the light and dark moth populations? d.As the trees continue to darken as a result of the Industrial Revolution, according to the data, what will likely occur to the moth population as a whole? What type of selection occurs? e.Hypothetically, if the trees became half light and half dark, what would you expect would you expect in the light and dark moth populations. What type of selection would take place? Answer Key: a.Dark moths: (71-50)/(5-0) = 4.2; roughly 4.2% per generation b.Light moths: (16-50)/(5-0) = -6.8; roughly -6.8% per generation c.The dark moths have a positive growth rate, because they have the phenotypic advantage of dark color, which can be utilized as camouflage with the dark tree bark. The light moths demonstrate a negative growth rate, because they are more susceptible to predators, due to their lack of proper coloration for camouflage. The dark moth populations are better able to survive than the less adapted white moth populations. d. Natural selection will favor darker moths that can better blend in with the tree bark. This favoring of only extreme, dark color, is a directional selection. e. Instead of either a dark or light color being favored by natural selection, an intermediate color between light and dark could be selected for. The two extremes, light and dark, could “merge” to form a better intermediate adaption through stabilizing selection.

LO 4.24: The student is able to predict the effects of a change in an environmental factor on gene expression and the resulting phenotype of an organism. SP 6.4: The student can make claims and predictions about natural phenomena based on scientific theories and models. Explanation and Connection: Natural selection can be defined as the reproduction of individuals that are best adapted to the environment in which they currently live. Natural selection can be caused by several types of isolation, such as habitat isolation, temporal isolation, and mechanical isolation. It can also be caused by a sudden change in an environmental factor, like precipitation. For example, the differing beaks of finches on the Galápagos Islands is due to a drought that occurred on one of the islands. When the precipitation drastically decreased, many of the fruit-bearing plants that provided food for the finches died, resulting in a lack of fruit. The finches with straighter, stronger beaks that were better adapted to eating cactus seeds were able to reproduce and pass of this favorable trait because they were able to adapt to the new food source. The finches with rounded beaks better adapted to eating fruits were unable to reproduce and pass on the trait for a rounded beak because they could not eat enough food to survive. Multiple Choice Question: A population of finches on the Galápagos Islands is exposed to a severe drought for several mating seasons. The lack of precipitation results in a sharp decline of fruit- bearing plants and the insects that eat them. The impact on the finch population would be: I.The finches would die out since the lack of food would prevent them from surviving to reproduce II.The finches with beaks better adapted to eating hard seeds that can withstand the drought will survive to reproduce because of the abundance of food in comparison with the fruit-bearing plants and insects, while the finches with beaks not adapted to eating the hard seeds will die out III.The finches with the genotype for larger beaks adapted to cracking hard seeds will survive the drought to reproduce and the finches without the genotype will die out. A.I only B.II only C.II and III D.I, II, and III FRQ: The European Corn Borer is a moth that flies around at night and lays eggs on the undersides of corn leaves. When the larvae hatch, they feed off of the corn leaves, boring holes through the leaves, eventually killing the corn plant. A farmer sprays insecticide to kill the larvae, but several weeks after he sprays, there are more larvae, and the insecticide is no longer effective. A.Explain why several weeks after the farmer sprays, there are still European Corn Borer larvae on the leaves. B.Propose one biological and one chemical solution to reduce the Corn Borer populations.

Multiple Choice Question: A population of finches on the Galápagos Islands is exposed to a severe drought for several mating seasons. The lack of precipitation results in a sharp decline of fruit-bearing plants and the insects that eat them. The impact on the finch population would be: Multiple Choice Question: A population of finches on the Galápagos Islands is exposed to a severe drought for several mating seasons. The lack of precipitation results in a sharp decline of fruit-bearing plants and the insects that eat them. The impact on the finch population would be: I. The finches would die out since the lack of food would prevent them from surviving to reproduce II. The finches with beaks better adapted to eating hard seeds that can withstand the drought will survive to reproduce because of the abundance of food in comparison with the fruit-bearing plants and insects, while the finches with beaks not adapted to eating the hard seeds will die out III. The finches with the genotype for larger beaks adapted to cracking hard seeds will survive the drought to reproduce and the finches without the genotype will die out. A. I only B. II only C. II and III D. I, II, and III Explanation: I is incorrect because only the finches not adapted to eating hard seeds and cacti. III is incorrect because even though some of the finches may have the genotype for larger beaks, they must have the phenotype of larger beaks for it to be of any use to them. Some of the finches may have larger beaks as an unexpressed allele, they will not have the phenotype of a large beak, and will die from starvation like all the other finches not adapted to eating hard seeds or cacti. II is correct because the finches that have the phenotype that is best suited for a dryer environment will be most successful during a drought. The finches with slightly larger beaks will be slightly more successful in finding food, meaning they have a better chance for reproducing and passing on the gene for a larger beak. FRQ: The European Corn Borer is a moth that flies around at night and lays eggs on the undersides of corn leaves. When the larvae hatch, they feed off of the corn leaves, boring holes through the leaves, eventually killing the corn plant. A farmer sprays insecticide to kill the larvae, but several weeks after he sprays, there are more larvae, and the insecticide is no longer effective. A.Explain why several weeks after the farmer sprays, there are still European Corn Borer larvae on the leaves. B.Propose one biological and one chemical solution to reduce the Corn Borer populations. Answer to FRQ: A.After the farmer sprays the insecticide, many of the larvae are killed, but the ones that have a slight resistance to the insecticide were able to survive it and reproduce, passing on the trait for resistance to the insecticide. These insects will go on to produce more offspring with resistance to the insecticide, until eventually all of the population in the corn field is resistant to the insecticide, rendering it useless. B.One biological solution to reduce the European Corn Borer population is to introduce a natural predator, such as a ladybug to keep the population lower to minimize the crop loss at the end of the growing season. The ladybugs will eat the European Corn Borers, reducing their population and not harming the corn plants. Additionally, the ladybugs will eat other pests that are not necessarily known to the farmer. One chemical solution to rotate the type of insecticide used to kill the Corn Borers. By alternating which insecticide is used, the Corn Borers will have a harder time building resistance to the insecticides, since the ones resistant to the first one sprayed may not be resistant to the second one sprayed.

LO 3.47: The student is able to create a visual representation of complex nervous systems to describe/explain how these systems detect external and internal signals, transmit and integrate information, and produce responses. SP 1.1: The student can use representations and models to communicate scientific phenomena and solve scientific problems. Explanation: The nervous system is the basis for all responses to external and internal stimuli in the body. The stimulus is received through various ways (external being things like touch, taste, smell, sight, and sound; internal being hormones and other things the body might need to respond to). That stimulus is received by a sensory neuron which passes the electrical signal to an interneuron (for example in the spinal cord), where the signal is integrated and passed to the motor neuron which sends the signal to the effector, causing the muscle to move. The process of integration involves the accumulation of action potentials through the synapse. Excitatory impulses depolarize the membrane potential towards the threshold point, opening Na+ channels to cause the positively charged ions to go into the cell, making it less negative. Inhibitory impulses hyper-polarize the membrane away from the threshold point, opening K+ channels to cause the positively charged ions to go out of the cell, making it more negative. These impulses accumulate through either temporal summation or spatial summation, which causes the action potential to fire from the axon hillock and make its way down the axon towards the next synapse. After the signal passes through, the Na+/K+ pumps re-polarize the membrane. SlidePlayer: Dr. Plexus- The Nervous System II http://slideplayer.com/slide/7627546/ FRQ: Doctors typically check their patients’s reflexes by tapping a certain spot on their knees. a.Name the three types of neurons that this signal will pass through. b.After the stimulus is received, describe the biochemical process by which the excitatory signal is passed from neuron to neuron. c.Consider a condition that involves the deletion of a gene that codes for the Na+/K+ pump. Make a prediction as to whether the reflex occurs in a patient with this condition? MC Question: A research lab conducts an experiment where they replace the interneuron in the spinal cord with a sensory neuron in an animal model. Will the reflex still occur after the stimulation? A)Yes, because all neurons use the same Na+ and K+ channels to pass signals along the axon B)Yes, because the neurotransmitter will be the same throughout the process as it is the same signal passing through C)No, because the synaptic cleft will not the be same size that is needed for the correct neurotransmitter to cross D)No, because the neurotransmitters that cross at each synapse and the receptors on the other side are particular to each type of neuron

Answer Key FRQ: Doctors typically check their patients’s reflexes by tapping a certain spot on their knees. a.Name the three types of neurons that this signal will pass through. b.After the stimulus is received, describe the biochemical process by which the excitatory signal is passed from neuron to neuron. c.Consider a condition that involves the deletion of a gene that codes for the Na+/K+ pump. Make a prediction as to whether the reflex occurs in a patient with this condition? a.The three types of neurons that the signal passes through are the sensory neuron, the interneuron, and the motor neuron. b.The neuron fires a signal when its axon hillock determines that the threshold has been reached. This occurs by a depolarization of the membrane, where Na+ channels open up and allow the positively charged ions to flow through and make the inside of the membrane less negative. Once the threshold has been passed and the action potential is fired, the signal travels along the axon by the process of depolarization (and subsequent hyper- polarization by allowing K+ ions to flow out of the membrane, making it more negative) until it reaches the synapse that connects it to the next neuron. There, the depolarization of the membrane opens up channels allowing the specific neurotransmitter to get inside the membrane in vesicles. From there, the vesicles fuse with the cell membrane and go into the synaptic cleft, and then are received by transmitters on the other side which signal the entire process again in the other neuron. c.The reflex would most likely occur the first time, but not the second. The depolarization occurs the first time the signal goes through, but because the neurons are missing the Na+/K+ pump they cannot repolarize the membranes to pass the next signal whenever stimulus is received again. MC Question: A research lab conducts an experiment where they replace the interneuron in the spinal cord with a sensory neuron in an animal model. Will the reflex still occur after the stimulation? A)Yes, because all neurons use the same Na+ and K+ channels to pass signals along the axon B)Yes, because the neurotransmitter will be the same throughout the process as it is the same signal passing through C)No, because the synaptic cleft will not the be same size that is needed for the correct neurotransmitter to cross D)No, because the neurotransmitters that cross at each synapse and the receptors on the other side are particular to each type of neuron Explanation: Different types of neurons have different types of receptors to receive different types of neurotransmitters. If the interneuron is replaced by another sensory neuron, the first sensory neuron will release a certain type of neurotransmitter that the other sensory neuron likely does not have a receptor for. Likewise, when the second sensory neuron releases the neurotransmitter to the motor neuron, it will release the wrong type of neurotransmitter that the motor neuron does not have a receptor for.

Learning Objective 1.17: Stephen Markwalter A. Learning Objective 1.17: The student is able to pose scientific questions about a group of organisms whose relatedness is described by a phylogenetic tree or cladogram in order to (1) identify shared characteristics, (2) make inferences about the evolutionary history of the group, and (3) identify character data that could extend or improve the phylogenetic tree. B. Science Practice 3: The student can engage in scientific questioning to extend thinking or to guide investigations within the context of the AP course. 3.1: The student can pose scientific questions. C. The learning objective attempts to assist students in making questions about relating visual representations of evolution to their respective inferences concerning the principles of evolution and common ancestry. D. Five organisms, A, B, C, D and E, are shown in the cladogram below. Which of the following scientific questions could be effectively answered by the cladogram? A.Which traits caused the early divergence of A from the other organisms? B.What genetic mutations occurred in order to make each organism diverge from their common ancestors? C.Of the five organisms, which two are the most closely related? D.Exactly how many millions of years ago does each divergence occur? FRQ The evolutionary relationships between five organisms are visually represented in the cladogram below. a.Based on the cladogram, identify the organism that is known as the outgroup of the five organisms and identify the organism that is the most closely related to the whale in the cladogram. For each identification, explain the reasoning that allowed you to arrive at your conclusion. b.Identify TWO pieces of evidence that could potentially help a researcher improve the above cladogram by revealing new evolutionary relationships. For each identification, discuss why each piece of evidence would be a strong and effective method of gathering information.

Answer Key Multiple Choice: A is incorrect because although some cladograms indicate which traits are the primary reasons for the divergence of organisms from their respective common ancestors, this cladogram solely shows the relative relationships between each organism. B is incorrect because the cladogram in question only visually represents the apparent and relative evolutionary relationships between each of the five organisms, not exact changes in DNA sequences. C is correct because cladograms express the evolutionary history and relationships that are present between the organisms in the diagram; that is, from each “node” in the cladogram, one is able to effectively tell which organisms are more related than others. In this case, organisms E and D are the most closely related. D is incorrect because although cladograms give an indication of when each divergence occurs, this is only a relative time measurement. The times at which each organism diverges are not explicitly specified in the cladogram. FRQ: A. The seal is the outgroup of the five organisms, and the hippopotamus is the organism that is the most closely related to the whale. The outgroup is able to be deduced by observing the cladogram and verifying which of the “branches” of the diagram is the longest; the longest branch serves as the outgroup, as it has the most differing traits from all of the other organisms. Since the hippopotamus is positioned directly next to the whale in the diagram, it is the most closely related to it since the cladogram implies that the two share the most traits. B. Four possible pieces of evidence are fossils, homologous structures, similarities in embryo morphology and DNA sequences. A fossil shows concrete evidence of a common ancestor and the resulting evolutionary relationships that arise from the ancestor. DNA sequences can show similarities in nucleotides which can imply descent from a common ancestor. The form of embryos and any similarities in their forms could also be indicative of the presence of a common ancestor; the similarities in homologous structures of the adult organisms would also be valid evidence of a common ancestor.

LO 3.29: The student is able to construct an explanation of how viruses introduce genetic variation in host organisms. SP 6.2: The student can construct explanations of phenomena based on evidence produced through scientific practices. Explanation: The lysogenic cycle is that in which a phage inserts its DNA into the bacterial chromosome of a host cell, integrating itself within the cell’s own DNA. As the cell reproduces normally and replicates its DNA, the inserted prophage following along the cell division cycle to pass its information to the newly produced daughter cells. If conditions allow the lysogenic cycle, not lytic cycle, to continue and repeat itself, then the DNA within the specific cells will permanently alter the chromosome of the cells from that point on, leading to potential mutations and/or variations within the cells, which will ultimately express itself through the organism as a whole, (noticeable or not). Understanding this process and how viruses can cause genetic variation within host organisms can allow one to study these occurrences in controlled environments to explain any differences between an infect host and a non-infected host. Once the infection is supported with evidence that it exists within the cell’s chromosome, the student can utilize external observation, gel electrophoresis, and/or RFLP analysis as scientific practices to understand these mechanisms working inside organisms. MC Question: A cell has two options influenced by a number of factors once a virus has inserted its DNA into the cell, either it can enter the lysogenic or lytic cell. With your knowledge of how the lysogenic cycle works, could genetic variation still be seen within an organism if it underwent the lytic cycle? A)No because the lysing of the cell during the lytic cycle expels the phage DNA from the host cell into the surrounding membranes of the other cells, therefore not giving it enough time or proper conditions to replicate into the chromosome of other cells. B)Yes because phages form inside the cells during the lytic cycle to be expelled from the cell and carry their DNA to other cells to infect them with the same DNA. C)No because the lysing of the cell during the lytic cycle prevents the cell from continuing the reproduction process, therefore it cannot pass on genetic information to daughter cells. D)Yes because, when the phage first inserts itself into the host cell, some DNA escapes and spreads along the communication pathways between cells to enter through the membranes of other cells without physical infection through a phage. https://biotechkhan.wordpress.com/c ategory/virology/bacteriophages/ FRQ: The lysogenic cycle is a process in which a bacterial cell is infected by a phage and undergoes change to its chromosome. a)Describe the process of the lysogenic cycle. b)Discuss the three different methods by which genetic recombination occurs through bacterial cells. i] transformation ii] transduction iii] conjugation c) Viruses can spread through a number of ways. Define vertical and horizontal transmission and give an example of each.

Answer Key MC Question: The correct answer is C) No because the lysing of the cell during the lytic cycle prevents the cell from continuing the reproduction process, therefore it cannot pass on genetic information to daughter cells. Explanation: If the cell is ruptured before it can enter any reproductive stages, then the DNA is kept inside the phages that form within the host cell as the cell itself ruptures. Though these phages can infect other cells and potentially start the cycle over again, not true genetic information is passed through the lytic cycle. Only the lysogenic cycle, in which the cells reproduce, illustrates continual change in the cells that affect an organism overall. FRQ: a) The cycle begins when the genetic material inserted into the cell initially integrates into the bacterial chromosome. The cell then begins the process of division (meiosis /mitosis) and the genetic material incorporated into the chromosome then splits between the daughter cells to eventually create a population of cells carrying the phage DNA. b) i] Transformation is the uptake of external DNA by a cell. This uptake of foreign DNA contains fragmented DNA segments, which incorporate themselves into the existing bacterial chromosome. ii] Transduction is the transferring of DNA between cells through phages emitted by an infected cell. A fragment of previously inserted DNA can be carried to a different host cell, allowing the insertion of that fragment to alter another cell’s bacterial chromosome. iii] Conjugation is the direct transfer of genetic material through a sex pili attached to one host cell extending to another. This attachment draws the cells closer together to exchange genetic information. c) Horizontal transmission is the spreading of a virus/disease to another organism indirectly, such as through the air, body fluids, etc. An example of this could be someone with the flu sneezing in an elevator and spreading the germs to the other occupants of the elevator. Vertical transmission is the spreading of a virus/disease through inheritance from a parent organism. These are not contagious infections, but they are incorporated into the phenotype of an organism’s parents which may or may not lead to inheritance of that disease. An example of this would be an organism’s parents passing down Kleinfelter Syndrome or Turner’s Syndrome to their offspring; these diseases are not spread through air or body fluids, but only through DNA.

LO 2.40 The student is able to connect concepts in and across domain(s) to predict how environmental factors affect responses to information and change in behavior. SP 7.2 The student can connect concepts in and across domain(s) to generalize or extrapolate in and/or across enduring understandings and/or big ideas. Explanation: Individuals in an environment can act on information and communicate it to others. For example, innate behaviors are behaviors that an organism inherits. These types of behaviors typically involve basic life functions like a caterpillar making a cocoon or a bird building a nest, both of which are necessary for the animal’s survival. In addition, learning can occur through interactions with the environment and other organisms. For example, Nettles grow bristling fur on the end of their pointed structure to keep other animals from browsing. Therefore, if a caterpillar were to were to wander onto the nettle, the nettle would interact with the caterpillar not allowing its leaves to be eaten by activating its chemical plant defenses and thus the caterpillar learns that this is not a possible food source for the future. Furthermore, these responses to information and communication of information are vital to natural selection. For example, in phototropism in plants, which is changes in the light source lead to differential growth, results in maximum exposure of leaves to the sun or the light energy source to perform photosynthesis. For example, in a forest where plants are crowded, the process of phototropism will direct the seedlings towards the sunlight that will power photosynthesis and allow the seedling to survive and grow and develop to eventually reproduce. Also, through the process of photoperiodism in plants, changes in the length of night regulate flowering and the plants preparation for winter. Thus the classification of short-day, long-day and day-neutral plants was necessary in order to allow the different plants to reach the necessary critical period of light or darkness to be able to flower and survive. An example of one of these plants would be an iris, a long-day plant that only flowers when the light period is longer than a certain number of hours necessary for the plant to flower. On another note, behaviors in animals are triggered by environmental cues and are vital to reproduction, natural selection and thus the animals survival. For instance, many animals must adapt to their environments by altering their physiological state known as torpor. Both hibernation and estivation are basic examples of torpor. During hibernation, an animal such as the Belding’s ground squirrel (see picture at top right), retreat to their burrow for the 8 months of cold weather while lowering metabolic rate and conserving energy. This allows the squirrel to avoid harsh winter conditions and survive to reproduce offspring of its own and pass down its favorable genes to the next generation. Finally, cooperative behavior within or between animal populations contributes to the overall survival of the populations. For example, this cooperative behavior is necessary because two species cannot coexist in a community if their niches are identical. Thus this differentiation of niches that enables similar species to coexist in a community together is called resource partitioning (figure at bottom right). An example of this would be 5 similar lizard species living in close proximity to each other use their resources slightly different, allowing them to coexist together. Therefore, the rate of survival for that lizard population is much greater. In all, organisms can be affected by their environment and these factors lead to responses to information and changes in behavior. (Figure 40.22) MC Question: Which of the following would not be an an advantageous adaptation of an animal to its environmental surroundings? A. The African lungfish burrows into the bottom of a riverbed until the dry season is over. B. Hummingbirds feed during the night, escaping predators, and go into a state of torpor during the warm afternoons. C. Chickadees feed during the day and go into a state of torpor during cold nights. D. A Belding’s ground squirrel retreats to its burrow in September to lower his body temperature and metabolic rate. FRQ: Answer all of the following questions completely and thoroughly. Diagrams or pictures alone are not sufficient. Explain how each of the following are vital to survival and natural selection of an organism. Identify and describe and example for each. A.Commensalism B.Mutualism C.Cryptic Coloration D.Batesian Mimicry http://www.slideshare.net/thelawofscience/population-growth-22514883

Answer Key MC Question: FRQ : Explain how 3 of the following are vital to survival and natural selection of an organism. Identify and describe and example for each. [6 points total {1pt for description and connection to survival/natural selection & 1pt for example} A.Chemical plant defenses [2pts] B.Mechanical plant defenses [2pts] C.Cryptic Coloration [2pts] D.Batesian Mimicry [2pts] Which of the following would not be an an advantageous adaptation of an animal to its environmental surroundings? A. The African lungfish burrows into the bottom of a riverbed until the dry season is over. B. Hummingbirds feed during the night, escaping predators, and go into a state of torpor during the warm afternoons. C. Chickadees feed during the day and go into a state of torpor during cold nights. D. A Belding’s ground squirrel retreats to its burrow in September to lower his body temperature and metabolic rate. Explanation: Answer A is correct because as the African lungfish burrows into the riverbed, eventually it will become encased in a sheath of mucous that hardens, allowing them to survive when the waterbed eventually dries out during the dry season. Answer B is incorrect because hummingbirds only go into daily torpor during the night time when it’s cold to survive on stored energy. The addition of the part about escaping predators was merely a distracter answer. Answer C is correct because just like the hummingbirds, chickadees feed during the daytime and go into a state of torpor at night to avoid cold temperatures and energy loss. Answer D is also correct because the Belding’s ground squirrel retreats to its burrow for a total of 8 months over the colder months and avoids cold conditions and lack of resources. The student had to connect different animals to their own environmental surroundings and predict the responses that would change their behavior. A.Commensalism is the interaction between species that benefits one of the species but does not harm or help the second species involved. A renowned example of this relationship would be that of the relationship between cattle egrets and water buffalo. Whenever the water buffalo graze, they stir up the insects on the ground and make it easier for the cattle egrets to easily find food, the insects. Thus as the buffalos graze, the cattle egret are in return aided in the acquiring of food while the buffalos, the herbivores, are unaffected by this event. Based on the interaction of commensalism, organisms are able to find easier ways to attain food resources and will be able to survive and reproduce. Over the beneficial years of the cattle egret following the bison, the effects of natural selection will come into play and these favorably acquired genes will be passed onto the next generation of egrets. B.Mutualism is an interspecific interaction in which both species benefit either positively or negatively. There is a mutualism based relationship between ant and the acacia trees from Central and South America. These ants feed on the sugar produced by the nectaries on the tree and the acacia benefit because the ants remove fungal spores, remove debris, and clip any other vegetation that grows nearby. Thus natural selection might favor evolution of such adaptations because by sacrificing one aspect, an organism is able to gain another and hence the relative reproductive success will increase. C.Cryptic Coloration, also referred to as simply camouflage, makes it difficult for a prey species to be spotted. For example, the canyon tree frog’s skin blends in with its environment making it extremely difficult to be hunted by a predator. Through natural selection of these favorable camouflage genes for skin color, the frog has been able to survive and reproduce to pass on its favorable genes to the next generation. D.Batesian mimicry allows one prey species to gain significant protection by mimicking the appearance of another. Generally, this involves a harmless or palatable species mimicking and harmful and unpalatable one. For example, the larva of the hawk-moth puffs its head up when its disturbed, which makes it look like the head of a poisonous snake. This mimicking of appearance allows the organism to protect itself from predators, thus surviving to reproduce and pass on its favorable genes to the next generation. [clearly there are other possible examples for A-D and points may be rewarded if the example is valid and supported with detail]

LO 3.40; The student is able to analyze data that indicates how organisms exchange information in response to internal changes and external cues, and which can change behavior. SP 5.1; The student can analyze data to identify patterns or relationships. Explanation; There are multiple ways in which organisms exchange information in response to internal changes and external cues. A few examples of this are the fight or flight response, predator warnings, protection of young, plant-plant interactions due to herbivory, and avoidance responses. The fight or flight response occurs when our senses undergo environmental stress, and the endocrine and nervous systems prepare the body to respond. The response will either be to stay and fight the threat, or to run and flee from the environmental threat. The cell communication that happens in this response creates a behavioral response by exchanging information. Predator warnings allow organisms to communicate to their predators and let them know that they are dangerous. An example of this is aposematic coloration, where the organism conveys that they are dangerous to their predators through their bright, threatening colors. The coral snake is a prime example of how predator warnings work to communicate information to other organisms, changing behavior. By observing and analyzing coral snakes, scientists have learned that their coloration serves as a useful mechanism to change the behavior of their predators, thus preventing the predators from attacking. The same relationship between predator and prey can be observed with the poison dart frog and its predators. The frog communicates that it is poisonous through its bright blue coloration, and this warns the predator not to attack. The protection of young involves the exchange of information between organisms in response to cues. With altruistic behavior, the older organism protects the younger by risking its life to warn of danger. Belding’s ground squirrels give sufficient data that altruistic behavior is an effective way to protect young and ensure that the best-fit genes get passed to the next generation. When studying the ground squirrels, it is observed that there is a pattern of altruistic behavior every time a predator strikes. A squirrel lets out an alarm call that alerts the other squirrels to seek shelter. The squirrel risks its life to protect its young. Plants have interactions that protect them from being eaten by herbivores. Neighbor plants may reduce herbivory on individuals by making them less accessible (concealment). Along with this, plants can utilize an avoidance response by growing in places where they can easily avoid herbivores. MC question; A hawk has spotted a cluster of ground squirrels, and a few squirrels look up to see the bird flying towards them. Which behavior will l most likely occur next? a)The squirrels will group off into families and run up the nearest trees. b)The leader male squirrel will send out a bark to call upon a group of “warrior” male squirrels to fight the hawk. c)One squirrel will send out an loud alarm call to warn the others to seek cover underground. d)The hawk will notice the threatening dark colors on the squirrels and leave to find different prey. A flock of hawks is circling above am ecosystem of multiple species of potential prey. a.A squirrel notices the hawk. Explain how the fight or flight response would benefit the squirrel in this situation. b.One hawk swoops in to swipe up a snake but freezes when it sees the black and red colors on it. What kind of exchange of information between the predator and prey has just taken place to prevent the attack? c.A female chipmunk hides her newly born offspring in a nearby tree trunk, but there is no room for her so she guards it. What kind of behavior is she exemplifying? d.A hawk captures a ground squirrel. How did this squirrel get attacked and what communication was likely taking place with this squirrel? This shows the survivorship curve for male and female squirrels. The males have lower survivorship because they exhibit the altruistic behavior to exchange information with others. http://slideplayer.com/slide/5313230/

Answer Key MC question; C. This is the correct answer because the squirrel would exhibit altruistic behavior. One squirrel will most likely put his life at risk for the benefit of his species. The other ground squirrels will hear the alarm and will be signaled to seek shelter from the predator. However the squirrel who is giving the alarm is attracting attention to himself and will be killed if he is not fast enough to run to underground cover when the hawk swoops in for him. FRQ; A. The endocrine and nervous system of this squirrel will receive the stimulus that there is a threat and will undergo the fight or flight response. The cell communication inside the squirrel will determine if the squirrel should stay and try to protect himself or if he should run and flee. In this particular situation, the flight response would benefit the squirrel, this way he could run and seek cover underground with the other Belding ground squirrels. B. A Predator warning has just been delivered from the snake to the hawk. The aposematic coloration of the snake has warned the hawk that the snake is dangerous, and this exchange of information will most likely stop the hawk from killing the prey. C. She is protecting her young. The chipmunk is willing to put herself at risk for the survival of her young. D. This Belding ground squirrel most likely got attacked because he was exhibiting altruistic behavior. This was probably the squirrel that gave out the warning alarm to protect and warn the other squirrels. This squirrel risked his life for the benefit of the other organisms around him, and this exchange of information led to the survival of the other squirrels, but his ultimate demise.

LO 4.21: The student is able to predict consequences of human actions on both local and global ecosystems. SP 6.4: The student can make claims and predictions about natural phenomena based on scientific theories and models Explanation: An ecosystem consists of all the organisms in a particular area, coupled with the abiotic factors that they interact with. Ecosystems surround us, and every part of the world around us is part of an ecosystem. In ecosystems, biotic factors (plants, animals, other organisms) interact with abiotic factors (water, air, minerals) in the area. This serves to create a more balanced environment. The organisms, or biotic factors, in the ecosystem are able to adapt and evolve over time to obtain more favorable traits for the survival of the population of that species and make better use of the resource available to them in the ecosystem. The one species that is capable of disrupting this balance of the environment, however, is humans. Humans disrupt and alter ecosystems everywhere, on both a local and global scale, every single day. These disruptions happen extremely often, even when we don’t realize it. One of the major ways that humans disrupt many natural ecosystems is through the burning fossil fuels in vehicles and for electricity in housing and residential complexes, which releases excess greenhouse gases (such as CO 2 ) into the atmosphere, which disrupts the carbon cycle in the surrounding ecosystems. Humans also disrupt ecosystems through the introduction of invasive species to curb the population of other species that have a slightly negative effect on humans, and this causes huge interruptions in the natural order of balance in these ecosystems. These are only two of the many ways in which humans disrupt the ecosystems around them. Multiple Choice Question Which of the following is likely NOT a result of human interactions with the environment? A) Decrease in a particular species due to predation B) Gene mutations leads to development of a new species C) Increase in carbon in the atmosphere leads to increased temperature in the area D) Degraded land as a result of agriculture and depletion of soil nutrients Free Response Question A)Identify and discuss two different ways in which humans have impacted the tropical rain forest ecosystem. B)For one of the ways mentioned above, describe how the human impact affects the organisms in the tropical rain forest.

Multiple Choice Question Which of the following is likely NOT a result of human interactions with the environment? A) Decrease in a particular species due to predation B) Gene mutations leads to development of a new species C) Increase in carbon in the atmosphere leads to increased temperature in the area D) Degraded land as a result of agriculture and depletion of soil nutrients Explanation A decrease in a particular species due to predation is often caused by the introduction of an invasive species, which are often introduced to ecosystems by humans, so the answer is not (A). Increased temperature as a result of increased carbon is an example of greenhouse gas emissions, which are often released from cars and other vehicles driven by humans, so it is not (C). Degraded land and depletion of soil nutrients is often the result of agricultural practices by farmers, so the answer is not (D). This leaves only option (B), since genetic mutations that lead to new species developing are not caused by human interactions with the ecosystem, but instead caused by DNA changes within specific organisms. Free Response Question Identify and discuss two different ways in which humans can impact an ecosystem. Sample Answer 1)One of the major ways in which humans have an impact on an ecosystem is through the emission of greenhouse gases, particularly through emissions from vehicles such as cars and trucks that are driven by hundreds of millions of people every day. This involves the release of primarily carbon dioxide (CO 2 ) into the atmosphere, which results in a disruption of the carbon cycle in the ecosystem, since the excess carbon cannot be photosynthesized by the plants in the ecosystem. This excess carbon in the atmosphere also results in the greenhouse effect, in which the CO 2 keeps heat from the sun from escaping the atmosphere and thus results in global warming. 2)Another way in which humans have an impact on an ecosystem is through the introduction of invasive species to the ecosystem to curb populations of species that have negative effects on humans, such as insects that disrupt agricultural cycles for farmers. The introduction of these invasive species to certain ecosystems will result in disruptions to natural predator/prey relationships, and likely resulting in major changes to normal ecosystem cycles. ANSWER KEY

LO 3.26 The student is able to explain the connection between genetic variation in organisms and phenotypic variation in populations. S.P. 6.5 The student can evaluate alternative scientific explanations. https://www.google.com/url?sa=i&rct=j&q=&esrc=s &source=images&cd=&cad=rja&uact=8&ved=0ahUK Ewja1aqMtq3MAhWOZj4KHW8aD3kQjRwIBw&url=h ttp%3A%2F%2Fblogs.plos.org%2Fdnascience%2F201 5%2F08%2F13%2Fdisappearing-syndrome-genetic- counseling-textbook-coverage%2F&bvm=bv. FRQ: In a population of 100 mice, there are 30 white mice, 20 black mice, and 50 gray mice. Based on the information answer the following questions: a.What is the likely reasoning for the color distribution of mice in this given population? b.What natural disaster could have caused this particular distribution of mice color to occur? Explanation: Genetic variation is what gives organisms the ability to have unique characteristics. Genetic variation is what leads to phenotypic diversity in populations that allow certain characteristics to be favored over others. One source of genetic variation is mutations. A chromosomal mutation like trisomy 21 is what causes Down Syndrome in the population. Sickle cell disease is another caused by genetic mutation and leads to differences in the phenotypes of blood cells. Another source of genetic variation is sexual reproduction. Each organism has two alleles for each trait and meiosis allows these alleles to be recombined for the next population generation. The different combinations of alleles like homozygous dominant, heterozygous, and homozygous recessive is what allows different phenotypes for traits. MC Question: A father is a carrier of cystic fibrosis and the mother is homozygous dominant, what is the chance that their child will have cystic fibrosis? (a homozygous recessive trait) A) 0% B) 25% C) 75% D) 50%

Answer Key: A father is a carrier of cystic fibrosis and the mother is homozygous dominant, what is the chance that their child will have cystic fibrosis? (a homozygous recessive trait) A) 0% B) 25% C) 75% D) 50% Explanation: The answer is zero percent because when you cross a homozygous dominant and heterozygous, the resulting offspring would have a 50% chance of not having cystic fibrosis and a 50% chance of being a carrier for the disease, thus the resulting offspring have a zero percent chance of having the disease. FRQ: In a population of 100 mice, there are 30 white mice, 20 black mice, and 50 gray mice. Based on the information answer the following questions: a.What is the likely reasoning for the color distribution of mice in this given population? b.What natural disaster could have caused this particular distribution of mice color to occur? Explanation: a.Natural selection favored the offspring that were gray in the environment, thus any offspring that were not gray were not able to survive and reproduce. b.There was a volcanic eruption in the habitat that lead to the primary color of the mice environment to be gray. This allowed natural selection to play its part in favoring those mice that had a gray pigment. Therefore, the mice without the gray color were selected against and resulting in a decrease of the white and black mice.

Explanation of LO 2.26: Analyzing data to form a phylogenetic tree, is based on the differences in amino acids. The lower in difference in amino acids makes the two organisms closer, in relation to the other organisms given. With Homeostatic mechanisms, this is all coming from one ancestor. Just as Darwin looked at the Finches in the Galapagos Islands. Once the drought hit the islands, the normal thin layered seed that the short beaked finches used to eat, where no longer there. Only hard/thick layered seeds, to where the finches had to evolve to survive or die. This is a change in a population/organisms based on environmental conditions. Organisms may have common processes/features, which a common ancestor evolved to now spread among a wide range of organisms today. FRQ’s A.With the Data table, Draw a Phylogenetic Tree that shows the relationship of the organisms based on the differences in the amino acids, and Explain the relationship between the organisms. B.Based on the Data table, Describe in detail three types of evidence, (other than the proteins relationship), that can be used to describe the phylogenetic relationship of the organisms. C.Change, is critical, depending on the evolution of the species genomes. Give all Four Examples for mechanisms that result in genetic changes in the organism’s phonemes/genomes, and then Describe the evolutionary advantage of the genetic variation. LO 2.26 The student is able to analyze data to identify phylogenetic patterns or relationships, showing that homeostatic mechanisms reflect both continuity due to common ancestry and change due to evolution in different environments. SP 5.1 The student can analyze data to identify patterns or relationships. MC Question: Compare all the lizards given in the chart, which sequence would the lizards be placed to form a phylogenetic tree in relation to the Komodo Dragons Amino Acids count. Then find the explanation that follows the right answer. A.4,5,1,6,3,2 : The relation between the Reticulate Python and Tuatara, is too close for both of then not to be related to each other. B.5,4,6,1,3,2 : The relation between the Gecko and the Green Anaconda is only 20% off. C.5,2,3,1,4,6 : The relationship between the Green Anaconda and the Reticulate Python shares 4.2% difference out of 50% in common. D.5,2,3,6,1,4 : The relationship between the Tuatara and the Komodo Dragan Have a 3.5% difference. Green Anaconda 55.6% Komodo Dragan 95.3% Gila Monster 75.9% Reticulate Python 51.4% Tuatara98.8% Gecko30.2% 1 2 3 4 5 6 % of Relationships of Amino Acid # of Amino Acids Differences in the Organisms Url: http://evolution. berkeley.edu/ev olibrary/article/e vo_24

FRQ’s: A) MC Question: 1) Compare all the lizards given in the chart, which sequence would the lizards be placed to form a phylogenetic tree in relation to the Komodo Dragons Amino Acids. Then find the explanation that follows the right answer. A.4,5,1,6,3,2 : The relation between the Reticulate Python and Tuatara, is too close for both of then not to be related to each other. B.5,4,6,1,3,2 : The relation between the Gecko and the Green Anaconda is only 20% off. C.5,2,3,1,4,6 : The relationship between the Green Anaconda and the Reticulate Python shares 4.2% difference out of 50% in common. D.5,2,3,6,1,4 : The relationship between the Tuatara and the Komodo Dragan Have a 3.5% difference. Answer Key Explanation of MC Question: With looking at an Amino Acid percentages in a graph, the one with the most similarity's will be the common ancestor of the Phylogenetic Tree, making that organism the base/trunk of the tree. Since the question asked which is closely related to the Komodo dragon’s Amino Acids, the Tuatara has a 98.8% similarity to the other organisms, making the base of the tree start with the Tuatara, then leading into the Komodo Dragon, and so on. A)The Relationship between the Blue whale and the walrus is only a 10 amino acid difference, but to all the other organisms the difference are grater the 10 making the blue whale be first on the phylogenetic tree. Then with the Hippopotamus and Rhinoceros having a difference of only 1 amino acid, based on the data the Hippopotamus and the Rhinoceros must be related. With only one difference the Rhinoceros must branch off of the Hippopotamus. Then with having some closer simulators to the other organisms but farther away from the Blue Whale the Lion will be next after the Hippopotamus and Rhinoceros. Fallowed by the Lynx, to making the top of the tree final. With fewer relations to the Blue Whale the Lynx is placed on top of the phylogenetic tree. B)Looking at embryonic development is one type of evidence to show the relationship between the organisms. The embryonic is normal used for mammals. This supports relationship to a common ancestor. Behavior is another way to determine where the organism need to be place on the phylogenetic tree. Fossils are another way to see if the organisms are related based on the bone structure, and formations of the bones. C)The four mechanisms of evolutionary are as stated, Natural selection, Genetic Drift, Mutations, and Gene flow. With all four of these the Natural Selection would go back to Darwin's finches. With Genetic Drift and Natural Selection, cannot operate unless genetic variation is present. With Gene flow, this is the migration of animals coming into/out of a population. With the Evolutionary advantages of gene variation, is that one organism can survive while the other one will be killed because it cant hind or not be seen my a predator. FRQ’s A.With the Data table, Draw a Phylogenetic Tree that shows the relationship of the organisms based on the differences in the amino acids, and Explain the relationship between the organisms. B.Based on the Data table, Describe in detail three types of evidence, (other than the proteins relationship), that can be used to describe the phylogenetic relationship of the organisms. C.Change, is critical, depending on the evolution of the species genomes. Give all Four Examples for mechanisms that result in genetic changes in the organism’s phonemes/genomes, and then Describe the evolutionary advantage of the genetic variation.

LO 3.36 The student is able to describe a model that expresses the key elements of signal transduction pathways by which a signal is converted to a cellular response. Explanation: There are three main stages of cell signaling. These stages are reception, transduction and response. In reception is the target cell’s detection of a signal molecule coming from outside the cell. The transduction stage converts the signal to a form that can bring about a specific cellular response. In response, the transuded signal finally triggers a specific cellular response. These receptors may include G- protein linked receptors. The binding of the signal molecule will in some way change the shape of the receptor. This is begin the transduction stage. The second messengers such as cAMP to pass alone the signal. This leads the final stage. The response is always specific to the signal molecule to started during the process. The examples of a response are the transcription of a gene into mRNA and the translation of mRNA into a protein, that has a specific function. SP 1.5: The student can re-express key elements of natural phenomena across multiple representations in the domain. MC: The receptors for a group of signaling molecules known as growth factors are often A) Receptor tyrosine kinases B) Ligand-gated ion channels. C)Cyclic AMP D)G-protein-linked receptors FRQ: Now you’re studying the different stages of cell signaling and cellular response. a)Briefly describe what are the three stages of cell signaling? b)Compare the differences between membrane- bound receptors and intracellular receptors. c)How can cells have different responses to the same signal?

Answer key: MC Question: The receptors for a group of signaling molecules known as growth factor s are often A) Receptor tyrosine kinases B)Ligand-gated ion channels C ) Cyclic AMP D)G-protein-linked receptors Explanation: Studies of receptor tyrosine kinases (RTKs) have revealed unexpected diversity in the mechanisms of their activation by growth factor ligands. The activation of intracellular signaling pathways following growth factor binding to RTKs. Also, the complex signaling networks downstream from RTKs and how alterations in these networks are translated into cellular responses. FRQ: Now you’re studying the different stages of cell signaling and cellular response. a) Briefly describe what are the three stages of cell signaling ? b) Compare the differences between membrane-bound receptors and intracellular receptors. c) How can cells have different responses to the same signal? a)Reception- ligand (signal molecule) binding to a receptor. Transduction- conversion of the received signal to a specific cellular response. Response- cell’s response to the signal. b) Membrane-bound receptors are located in the plasma membrane of a cell. Their ligands are water soluble and are too large to pass through the membrane without any assistance. These include G-protein-linked receptors, receptor tyrosine kinases, and ion channel receptors. Intracellular receptors are located either in the cytoplasm or in the nucleus. The signal must be able to freely pass through the plasma membrane in order to be able to bind to this type of receptor. Most molecules that bind to intracellular receptors are hydrophobic steroid hormones. When the signal molecule binds to the receptor, it stimulates the transcription of the gene into mRNA which is then translated into a specific protein. c)Different relay proteins, cross-talk with different signals and different receptor types.

LO 3.9 The student is able to construct an explanation, using visual representations or narratives, as to how DNA in chromosomes is transmitted to the next generation via mitosis or meiosis followed by fertilization. SP 6.2 The student can construct explanations of phenomena based on evidence produced through scientific practices. Explanation : In mitosis, the two main phases of the cell cycle are interphase and cell division. During Interphase (which cells spend 90% of their time in), cells go through the G 1 phase, the S phase, and the G 2 phase. The cell duplicates its DNA during the S phase and grows and prepares for cell division during the G phases. During prophase, the DNA in the form of chromatin begins to condense and becomes visible as chromosomes. The centrioles moves to opposite sides of the cell. During metaphase, spindle fibers align the chromosomes to the center of the cell to the metaphase plate. In anaphase, the spindle fibers pull the paired chromosomes apart at the kinetochores and move them to the opposite sides of the cell. During telophase, the chromatids are pulled fully to opposite sides of the cell and new membranes from around the daughter nuclei. Then the chromosomes disperse again and cytokinesis takes place. When it occurs in animal cells, cytokinesis occurs when actin around the center of the cell pinches the middle of the cell and the cell splits into two. In plant cells, a cell plate is formed between the two daughter cells. Mitosis forms two identical daughter cells to the parent cell. MC Question: During anaphase, the cell pulls chromosomes to opposite sides of the cell. What would happen to the resulting daughter cells if anaphase pulls an extra chromosome to one daughter cell and none for the other? A)The cell missing the chromosome would compensate by using the DNA from its mitochondria and the cell with the extra chromosome can silence it using Barr bodies. B)The cell missing the chromosome will most likely die whereas the cell with the extra chromosome will have an increase in expression in the genes from the extra chromosome. C)Both cells would remain in the G 0 phase of the cell cycle until they die of apoptosis. D)Both cells would complete cytokinesis and function relatively stable until they need to undergo mitosis. Then they would both be unable to clone themselves and natural selection would favor against them and they would die of apoptosis. FRQ: Mitosis and meiosis are cell cycles vital to life for many organisms on the planet. A)What are the differences between meiosis and mitosis? B)Name and explain one genetic disorder that could arise from an error in mitosis or meiosis C)What are some regulations of the cell cycle?

Answers MC Question: During anaphase, the cell pulls chromosomes to opposite sides of the cell. What would happen to the resulting daughter cells if anaphase pulls an extra chromosome to one daughter cell and none for the other? A)The cell missing the chromosome would compensate by using the DNA from its mitochondria and the cell with the extra chromosome can silence it using Barr bodies. B)The cell missing the chromosome will most likely die whereas the cell with the extra chromosome will have an increase in expression in the genes from the extra chromosome. C)Both cells would remain in the G 0 phase of the cell cycle until they die of apoptosis. D)Both cells would complete cytokinesis and function relatively stable until they need to undergo mitosis. Then they would both be unable to clone themselves and natural selection would favor against them and they would die of apoptosis. B is the correct answer because the cell missing the chromosome will die because it lacks important DNA to function through basic cell processes such as respiration. The cell with the extra chromosome will display an increase in expression from the genes because the DNA will go through transcription and translation until it is expressed. If the genes function to slow growth, the extra copy may be fatal to the cell. However, if the genes promote growth, the cell may grow uncontrollably, leading to cancer. FRQ: Mitosis and meiosis are cell cycles vital to life for many organisms on the planet. A)What are the differences between meiosis and mitosis? B) Name and explain one genetic disorder that could arise from an error in meiosis Trisomy 21 happens when nondisjunction occurs during meiosis. Nondisjunction is when sister chromatids fail to separate during anaphase so that when the telomeres pull the chromatids apart, they take two copies to one daughter cell and leave one daughter cell without. The resulting daughter cell with the extra chromosome develops Trisomy 21. C) What are some regulations of the cell cycle? The cell cycle has checkpoints, essential points during the cycle that regulate the process of passing from one stage to the next. It also has the G 0 phase, which halts the cell cycle. Growth factors are hormones or proteins that promote the division of the cell. Density-dependent inhibition is a process in which cells stop dividing when they are in contact with each other. There is also anchorage dependence, when cells must be attached to something in order to divide properly. EventMitosisMeiosis Homologous ChromosomesAlign in a row on metaphase plate Pair with each other during metaphase I. Alight after one another o metaphase plate during metaphase II Sister Chromatid SeparationAnaphaseAnaphase II Divisions12 Cells Produced2 genetically identical diploid 4 genetically different haploid

2 nd Period Review Projects. LO 3.33: The student is able to use representation(s) and appropriate models to describe features of a cell signaling pathway.

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2 nd Period Review Projects. LO 3.33: The student is able to use representation(s) and appropriate models to describe features of a cell signaling pathway.

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Presentation on theme: "2 nd Period Review Projects. LO 3.33: The student is able to use representation(s) and appropriate models to describe features of a cell signaling pathway."— Presentation transcript:

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