2Biology EOC Test is the second week back in January! You will be taking the test during your regularly scheduled science class5-6 scenarios40 questions total40-45% Cells, Genetics, DNA30-35% Populations and Ecology25-30% Evolution
3Test-taking Tips Go SLOWLY. Take your time, READ everything. Look at the pictures, charts and graphs…they are there for a reason.Pay attention to words in bold or italics. They are often clues to help you with the answer.
4Vocabulary Variables Validity Reliability Manipulated, responding, controlValidityWhat you did during the experiment (procedure) to obtain good data (NOT repeating, recording, calculating or measuring) making sure equipment is calibrated correctly for example.ReliabilityRepeat the experiment, multiple trials, obtain more data using same procedureMaking sure you have consistent resultsReliability is Repeatability
5Hypothesis If…then…because format I predict…reason Most importantly you have to include a reason for your statement.
6“Foaming Spuds” Conclusion writing practice 1. Answer the investigative questionWas your hypothesis supported/rejected and why2. Include supporting data from entire range of experiment (high and low)3. Explain how data supports or rejects your answer to investigative question4. Use scientific explanation to explain results/trends
7“Foaming Spuds” Procedure Re-write Create a procedure for a new variable that is being tested.Tips when re-writing a procedure…Procedure steps are logical and can be easily repeated by another personVariables are identified/impliedTwo controlsManipulated and Responding variableProcedure includes information about recording measurementsInformation about repeating trials is includedIncludes a validity measure not included in original procedure…
8Macromolecules “Giant Molecules” (polymers) Linked together with smaller subunits (monomers)CarbohydratesProteinsFats (lipids)
9Carbohydrates Compounds made of carbon, hydrogen and oxygen Used as a main source of energy for many organismsUsed for structural purposesBreakdown of sugars supplies energy for cell activities
10ProteinsMacromolecules that contain nitrogen, carbon, hydrogen and oxygenComposed of smaller molecules called amino acids20 amino acids found in natureEach protein has a specific roleReaction rates, cell processes, form bones and muscles, transport substances in and out of cells, fight disease
11Fats (lipids) Compounds made of carbon, oxygen and hydrogen atoms Glycerol + Fatty acid = LipidFats, oils, waxesSaturated and unsaturatedNot soluble in waterUsed to store energyParts of biological membranes and waterproof coverings
12Osmosis and DiffusionCell Membrane and Cell Wall regulate what enters and leaves cellsThis occurs during two processesOsmosisDiffusion
13DiffusionMovement of dissolved molecules from one side of cell membrane to anotherParticles move from an area where they are more concentrated to an area where they are less concentratedSubstances diffuse across a membrane without the cell using any energy
14Osmosis Diffusion of water across a selectively permeable membrane Most membranes selectively permeablesome substances can pass through and others cannotWater passes easily across most membranes
15Cells Cell: smallest unit of life Prokaryotic: no nucleus Eukaryotic:with a nucleusOrganelle: Specialized structure that performs important functions in the eukaryotic cell
16Organelles Cell Membrane Cell Wall Allows passage of oxygen, nutrients, and wastes in and out of the cellProvides protection and supportFound in plant and animal cellsCell WallProtects the plant cell, maintains its shape, prevents excessive water intakeFound only in plant cells
17Organelles Nucleus Chromosome Contains all genes (genetic information), chromatin, chromosomes and nucleolusControls protein synthesisFound in plant and animal cellsChromosomeTightly coiled strands of DNA and protein
18Organelles Chloroplast Mitochondria Site of photosynthesis, convert solar energy to chemical energyFound only in plant cellsMitochondriaSite of cellular respiration (generates energy)Convert chemical energy in food to a form cells can useFound in plant and animal cells
19Organelles Cytoplasm Ribosome Portion of the cell outside the nucleus Helps to maintain cellular shapeFound in plant and animal cellsRibosomeWhere proteins are madeFound throughout the cytoplasm
20Cell CycleCell cycle – The series of events that cells go through as they grow and divide.Has three main parts: Interphase, Mitotic Phase, Cytokinesis
21Cell Cycle (Mitosis)Interphase: Cells increase in size and make new proteins and organelles. Chromosomes are replicated.Mitosis: division of the nucleus. Divided into 4 phases.Cytokinesis: division of the cytoplasm.**Produces IDENTICAL Cells**
22DNA DNA is a double helix “twisted ladder” Sides of ladder made of sugar (deoxyribose)phosphateRungs of ladder made of nitrogenous basesAdenine, Thymine, Cytosine and Guanine
23DNA Base-Pairing DNA is made of molecules called: In a DNA molecule…. Adenine pairs with ThymineCytosine pairs with GuanineDNA is made of molecules called:NucleotidesSugar, phosphate and nitrogenous base (ATCG)
24Protein SynthesisGene: coded DNA instructions that control the production of proteins within the cellContain instructions for assembling amino acids into proteinsInstructions for making proteins comes from DNA…must first be converted into RNA to leave the nucleusDNA can’t leave the nucleus!
25Protein SynthesisProcess that produces protein using instructions from DNA (gene)Uses RNA as an intermediate step between DNA and proteinsTwo parts:Transcription (nucleus)DNA mRNATranslation (ribosome)mRNA protein (amino acid sequence)
26Genetics A gene is a section of DNA that forms a trait (protein). For example: Hair color, Height, ear lobes….Alleles are different forms of a gene.For example: brown hair, blond hair or Tall and short.You get one allele for each trait from your parents…
27Genetics RR = Dominant, Dominant - Homozygous Dominant allele – the allele that “wins”. We use a capital letter “R”Recessive allele – the allele that is hidden or loses . We use a lower case letter “r”.RR = Dominant, Dominant - HomozygousThis person can roll their tongueRr = Dominant, recessive – Heterozygous (hybrid)rr = recessive, recessive - HomozygousThis person can’t roll their tongue
28GeneticsEach organism must inherit a single copy of a gene (allele) from each of its parentsOrganisms have two copies of each gene (genotype 2 letters)Gametes (sperm and egg cells) each contain one copy of each gene
29Cells and Chromosomes Diploid: 2 copies of each chromosome All cells except sperm and egg cellsMitosisHaploid: one copy of each chromosomesperm and egg cells onlyMeiosisHumans 46 chromosomesReproductive cells have 23 chromosomes
30Meiosis What are the differences between mitosis and meiosis? Allows for genetic variation“Meiosis is the process in which the number of chromosomes per cell is cut in half”What are the differences between mitosis and meiosis?Mitosis produces two cells; cells are identicalMeiosis produces four cells; cells are unique; occurs only in sperm/egg cellsWhat are the similarities between mitosis and meiosis?First phase identical (meiosis phase 1); form of cell division
31Evolution Evolution – change over time It is the process by which modern organisms have descended from ancient organisms.How well an organism is adapted to its environmentCurrent scientific facts, observations and hypotheses all combine to create current evolutionary theorya well-supported, testable explanation of the biological diversity on Earth.
32Darwin’s Observations 1. Tortoiseslonger neck for sparse vegetation. Shorter neck where vegetation was more abundant.2. FinchesDarwin noticed that these birds have different shaped beaks, adapted to their food source (seeds)
35Evidence for Evolution Fossil Record – transitional fossils show us intermediate stages.Example: horse and camel
36Evolution by Natural Selection Definitions:1. struggle for existence – members of a species compete for resources2. Fitness – ability to survive and reproduce3. Adaptations – inherited characteristics that increase an organisms chance of survival.
37Variation Caused by mutations (changes in DNA sequences Results in physical or behavioral changesMay be beneficial or harmfulIncrease or decrease survival ratesInheriting different alleles from parents (causes individuals to look different)Results of meiosis are different every timeWhy we don’t look exactly like our siblings!
38Photosynthesis and Cell Respiration What happens during photosynthesis?Plants (autotrophs) use energy from sunlight to convert water and carbon dioxide into carbohydrates (energy) and oxygen6CO2 + 6H2O (light) → C6H12O6 + 6O2Reactants?Carbon dioxide (CO2) and Water (H2O)Products?Glucose—Sugar (C6H12O6) and Oxygen (O2)
39Photosynthesis and Cell Respiration Cellular respiration… is the process that releases energy by breaking down food molecules (glucose) in the presence of oxygen; occurs in heterotrophs6O2 + C6H12O6 6CO2 + 6 H2O + Energyoxygen+ glucose carbon dioxide + water+ energyCompare this to the equation for photosynthesis….what do you notice?
40Carbon Cycle Essential molecule that makes up all organisms Proteins, fats, carbohydratesCarbon is cycled…Between the atmosphere, land, water and organismsShort and long-term cycles
41Carbon Cycle In an ecosystem… 1. Plants convert carbon dioxide into carbohydrates (photosynthesis)2. Consumers eat producers, get carbon from carbohydrates (glucose)3. Consumers release carbon to atmosphere in carbon dioxide (breathing)
42Population EcologyPopulation – group of individuals of the same species that live in the same area.Population Density = # individuals/area
43Population GrowthPopulations may stay constant or change drastically from year to year.4 factors affect population size1. Natality – birth rate2. Mortality – death rate3. Immigration – movement of individuals IN4. Emigration – movement of individuals OUT
44Limiting Factors Limiting factors cause population growth to decrease. Density dependent – a factor that depends on population size. Occurs when populations are large and dense.CompetitionPredationParasitismDiseaseDensity Independent: A factor that affects all populations in similar ways, regardless of population size.Unusual weatherNatural disasterSeasonal cyclesHuman activity
45Exponential vs. Logistic Growth Exponential growth – population grows at a constant rate…with unlimited resources this will occur.Logistic Growth- occurs when growth slows or stops. -The largest number of individuals the environment can support is called the carrying capacity.
46Biomes and Biodiversity Biodiversity: the number of different species living in an ecosystemBiomes: Rainforest, Tundra, Savanna
47SustainabilitySustainability: using natural resources at a rate that does not deplete themCondition in which human needs are met in such a way that a human population can survive indefinitely“The traditional definition of sustainability calls for policies and strategies that meet society’s present needs without compromising the ability of future generations to meet their own needs.”(epa.gov)
48Sustainability Issues in Washington Invasive SpeciesNon-native species causing ecosystem damagePollution (air and water)Hydroelectric DamsOverfishingForest Management
49Field Study Scenario Include method for collecting data Imply a consistent sampling strategy“count at the same time every day”Identify one manipulated variableThree conditions to be credited (3 areas)Identify one responding variableWhat is being measuredRecord measurementsHow often, specific technique for recording measurementsRepeat trialsMultiple measurements, 2 sampling areasRecord environmental conditionsTemperature, weather, etc.Steps of procedure are logical