Ecology Big Ideas

Energy Energy flows through every ecological system – Inputs = what goes into the ecosystem – Outputs = what goes out of the system

Food Webs Increased biodiversity means a healthier ecosystem

Energy Transfer between Trophic Levels 10% Energy Transfer Producers make up largest biomass

Bioaccumulations Toxins cannot be removed and increase in amount between trophic levels

Carbon Cycle Cycles carbon through the ecosystem Contains photosynthesis and cellular respiration – Opposite chemical reactions

Nitrogen Cycle Cycles nitrogen through the system Bacteria takes nitrogen from the atmosphere and transfers it to plants

Population Growth Populations will grow exponentially if there are no limiting factors

Population Growth Populations will reach carrying capacity because of limiting factors which include: – Abiotic (non-living) Space & Water – Biotic (living) Food & Predators

Population Density Population Density is the number of living things in an area – Example: 500 moose in 10 sq. miles = 50 moose per mile

General Ecology Non-native species usually DIE in a new environment, some survive and take over if they have no predators

Sustainability Maintaining resources for future use Choices we can make now that support sustainability – Substituting renewable (?) for non-renewable (?) resources – Recycling – Using fewer resources

DNA and Genetics Big Ideas

DNA: deoxyribonucleic acid; is a code for your physical (phenotype) traits -  PHYSICAL TRAIT DNA & Genetics

Proteins: can be used to make body structures, hormones and enzymes – Enzymes act to speed up (catalyze) chemical reactions in the body Ex. Digestion of food, making DNA, and regulating glucose

Genetics Vocabulary Phenotype: What your physically look like Ex. Blue Eyes OR Brown Eyes Genotype: What your genes are Ex. Bb, bb, or BB

Vocabulary Dominant: Trait/gene that is shown Ex. BB = Brown Eyes Bb = Brown Eyes Recessive: Trait/gene that is hidden by a dominant gene Ex. bb = Blue Eyes Bb = Brown Eyes

Vocabulary Heterozygous: different genes – Ex. Bb for Brown Eyes Homozygous: same genes – Ex. bb for Blue Eyes

Punnett Square: used to predict offspring – Ex. Two heterozygous bunnies are crossed; black fur is the dominant trait – Phenotype ratio Ex. 25% white bunnies, 75% black bunnies – Genotype ratio Ex. 25% bb, 50% Bb, 25% BB F F f f FFFf ff

Punnett Square Practice: Small Whiteboards

Earlobes (E) A detached earlobe man (EE) has children with an attached earlobe woman (ee). 1)What are the possible genotypes (gene combination)? 2)What are the possible phenotypes (physical trait)?

A blue eyed male mates with a blue eyed female, what color eyes could the offspring have? – Blue eyes are recessive

A heterozygous tongue roller (Tt) mates with a non-tongue roller (tt), what percentage of their children will be tongue rollers?

Ear Wiggling (W) What is the probability (percentage) that two homozygous recessive people will have a child that can wiggle their ears? Can move ears = Dominant (although this may be variable) Can’t move ears = Recessive

A homozygous recessive female with freckles (f) mates with a homozygous dominant male without freckles (F), what genotypes could their offspring have?

What is the percent chance two heterozygous tongue roller will have a non-tongue roller offspring?

Mitosis and Meiosis and Evolution Big Ideas

Mitosis Mitosis: produces two IDENTICAL cells from one cell for growth and repair

Meiosis Meiosis: produces four UNIQUE sex cells for reproduction – Females: Eggs – Males: Sperm Allows for differences (variation) in populations

Mitosis and Meiosis

Evolution Evolution: change over time All living things are related to a COMMON ANCESTOR!!!

Evidence of Evolution Evidence: 1.Presence of Fossils found in rock layers 1.Homologous and Vestigial Structures Homologous: Similar Structures Vestigial: Unused structures; whale pelvis, human wisdom teeth

Fossil RecordHomologous Structures

Evidence of Evolution 3.DNA Comparisons Humans and mice are 99% similar in DNA, so they are closely related 4.Embryos Closely related organisms have similar embryos

DNA ComparisonsEmbryos

Natural Selection Natural Selection: “survival of the fittest, failure of the worst” – The “goal” of life is to survive and reproduce – Based on ability to survive in environment

Mutations in DNA: can (not always) lead to unique traits, which may help or hinder survival!! OrganismEnvironmentUnique Trait Bunny RabbitWinter CactusDesert CheetahAfrican Savanna ChameleonJungle PeacockMating Season

Mutations

Balancing Biological Systems Homeostasis

Homeostasis: regulation of systems to maintain balance Two things can affect homeostasis – Negative Feedback – Positive Feedback

Negative Feedback Negative Feedback: increase causes decrease, decrease causes increase – Ex. Automatic Thermostat: if temperature decreases in room, then the temperature increases – Negative ≠ bad

Positive Feedback: increase causes increase; decrease causes decrease – Ex. No shower for 2 weeks: smell from bacteria growth increases on a daily basis Positive ≠ good Positive Feedback

Negative or Positive Feedback?? Deforestation Regulating Body Temperature (too hot OR cold) Immune System Fighting Infection Body is Hungry P P N N

Choose two examples to complete a Negative Feedback Loop AND a Positive Feedback Loop Identify what HOMEOSTASIS would be Explain the STIMULUS that tells us homeostasis is not in balance Identify the CONTROL CENTER in the body (if there is one) that recognizes the stimulus Explain what RESPONSE occurs

Photosynthesis and Cellular Respiration Big Ideas

Photosynthesis & Cellular Respiration Photosynthesis and cellular respiration are opposite chemical reactions

Photosynthesis: plants take carbon dioxide (CO 2 ) and water (H 2 O) and make glucose (C 6 H 12 O 6 ) and oxygen (O 2 ) – Plants make their own food!!!!!!!!!!!!!!!!

Cellular Respiration: plants AND animals make energy (ATP) by transforming glucose (C 6 H 12 O 6 )and oxygen (O 2 ) into carbon dioxide (CO 2 ) and water (H 2 O) – CHEMICAL Energy in glucose is transformed into the energy to live (ATP) – Very similar to setting something on fire (combustion), which releases carbon dioxide (CO 2 ) into the atmosphere