ch 12 b

Question 1

microevolution

Answer 1

evolution at the molecular (gene) level; doesn’t necessarily involve formation of a new species

Question 2

gene variation

Answer 2

necessary for evolution; results from mutations in combination with sexual reproduction

Question 3

average heterozygosity

Answer 3

the average % of loci that are heterozygous

Question 4

geographic variation

Answer 4

difference in genetic composition of separate populations

Question 5

evolution

Answer 5

generation to generation change in a population’s frequency of alleles

Question 6

True or False: the hardy-weinburg only looks at one allele at a time

Answer 6

true

Question 6

5 unlikely situations of the Hardy-Weinburg Theorem

Answer 6

1. Allele and genotype frequencies never change from one generation to the next
2. mutations do not occur, so no new alleles rise
3. large population
4. Individuals mate randomly
5. individuals remain in their own population

Question 7

What are the three types of natural selection?

Answer 7

1. Directional Selection
2. Disruptive selection
3. Stabilizing selection

Question 7

What is the Hardy-Weinburg Equation?

Answer 7

p^2+2(p)(q)+q^2=1

Question 8

What is sexual dimorphism

Answer 8

Appearances of male and female differ in order to aid in reproductive success, can also scare off predators

Question 9

How do mutations lead to evolution?

Answer 9

A change in an organism’s DNA sequence can lead to a new allele to be introduced into a population. The effect of the mutation on a protein sequence can determine if a new trait is beneficial

Question 10

Genetic Drift

Answer 10

Change in allele frequency, eliminates alleles from a population and occurs by chance

Question 11

3 points of genetic drift

Answer 11

1. small population
2. only few reproduce and lose alleles in the next population
3. reduces variation

Question 12

What is the founder effect?

Answer 12

Occurs when a small group of individuals leaves home and isolates themselves into a new community

Question 13

What are the 2 examples of genetic drift?

Answer 13

1. Founder effect
2. Bottleneck effect

Question 14

What is the bottleneck effect?

Answer 14

results when a population reduces greatly over a short period of time

Question 15

Random mating and example

Answer 15

every individual has an equal chance of mating (ex. plants pollinated by wind)

Question 16

Non-random mating two factors

Answer 16

1. geological restrictions
2. attractions such as calls

Question 17

gene flow

Answer 17

moves alleles from one population to another, helps with genetic diversity

Question 18

directional natural selection

Answer 18

one extreme phenotype is the fittest and the environment doesn’t support others

Question 19

disruptive selection

Answer 19

two or more phenotypes are more fit and the intermediate phenotype

Question 20

stabilizing selection

Answer 20

extreme phenotypes are less fit than the intermediate optimal phenotype

Question 21

intrasexual selection

Answer 21

the members of one sex compete among themselves for access to the opposite sex (fighting)

Question 22

intersexual selection

Answer 22

the members of one sex choose their mates from among multiple individuals of the opposite sex (appearance)