SURE A+
✔✔What's the second part of Darwin's theory? - ✔✔2) Natural Selection: survival of the
fittest
-leads to adaptation (increased fitness)
✔✔What are the three ingredients for natural selection? - ✔✔1) Heritable variation: raw
material of evolution
2) Selection: preferential reproduction of those with variations more fit for the
environment
3) Time: required to generate and select new variants
✔✔What evidence supported Darwin's ideas? - ✔✔1) Fossil Record
2) Transitional Forms
-organisms in between ancestors and modern descendants
✔✔How are species placed in the evolutionary tree? - ✔✔1) age and location of fossils
2) comparative analysis of structural features
3) homology
4) direct observation
✔✔How do transitional forms change? - ✔✔In many ways at once
-ex: whale nostrils moved to the top of the head while the hind legs left
✔✔Describe homology - ✔✔Similarity resulting from common ancestry
-homologous structures and genes have similar structures but can differ in function
-result of divergent evolution
✔✔Describe analogous structures - ✔✔Structures with the same function but different
origins
-result of convergent evolution
✔✔Compare divergent and convergent evolution. - ✔✔Divergent- related species
evolve different traits to adapt
Convergent- unrelated species independently adapt similar traits
✔✔2 Types of Homology - ✔✔1) Vestigial structures
-remnants of homologous structures that no longer function but used to in ancestors
2) Sequence homology
-similarity between nucleotide or protein sequences
✔✔Evolutionary change is easily observed in organisms that are... - ✔✔-prolific
breeders
-under strong selective pressure (low chance of reproduction if unfit)
, ✔✔Factors that exert strong selective pressure... - ✔✔-food availability
-predatory behavior
-toxins (i.e. insects to pesticides)
✔✔What's the gene pool? - ✔✔all the genes & their alleles in a population
✔✔What's a population? - ✔✔members of one species that can interact with each other
✔✔What is micro-evolution? - ✔✔a change of allele frequencies in a gene pool
-doesn't really make new species
✔✔What is allele frequency? - ✔✔how common an allele is in a population
✔✔What is genotype frequency? - ✔✔fraction of a population with a given genotype
✔✔If predicted offspring frequencies hold up... - ✔✔the population is not evolving
✔✔For a population, the population's allele frequencies are equal to... - ✔✔gamete
genotype frequencies
✔✔What's the Hardy-Weinberg Equation and what does each variable represent? -
✔✔p^2 + 2pq + q^2 = 1
-p^2 = freq. of dominant homozygote
-q^2= freq. of recessive homozygote
-2pq= freq. of heterozygote
✔✔What is Hardy-Weinberg Equilibrium? - ✔✔when allele frequencies don't change
over time (not evolving)
✔✔What are the 5 requirements for Hardy-Weinberg Equilibrium? - ✔✔1) no net
mutation
2) random mating
3) no natural selection
4) large population size
5) isolated population (no migration)
*ALL MUST BE TRUE
✔✔What are the 5 mechanisms of evolution? - ✔✔1) Mutation
2) Genetic Drift
3) Gene Flow
4) Sexual Selection
5) Natural Selection