Evolution Exam 2

studied byStudied by 0 people
0.0(0)
learn
LearnA personalized and smart learning plan
exam
Practice TestTake a test on your terms and definitions
spaced repetition
Spaced RepetitionScientifically backed study method
heart puzzle
Matching GameHow quick can you match all your cards?
flashcards
FlashcardsStudy terms and definitions

1 / 30

encourage image

There's no tags or description

Looks like no one added any tags here yet for you.

31 Terms

1
Why is the Hardy-Weinberg model considered a null model?
It provides a baseline expectation for allele and genotype frequencies in a population that is not evolving. Deviations indicate evolutionary forces at play.
New cards
2
How is evolution defined from a population genetics perspective?
Evolution is the change in allele or genotype frequencies in a population over time.
New cards
3
What five conditions must be met for Hardy-Weinberg equilibrium?
No mutation, No natural selection, No gene flow (migration), Random mating, Large population size (no genetic drift).
New cards
4
What does it mean if a population is not in Hardy-Weinberg equilibrium?
It means one or more evolutionary forces are affecting allele frequencies.
New cards
5
Given allele frequencies B = 0.1 and b = 0.9, what are the expected genotype frequencies?
BB = 0.01, Bb = 0.18, bb = 0.81.
New cards
6
What factors cause deviations from Hardy-Weinberg equilibrium?
Mutation, natural selection, genetic drift, gene flow (migration), and non-random mating.
New cards
7
What is mutation-selection balance?

Equilibrium where new mutations arise at the same rate that selection removes them.

New cards
8
Why is mutation considered the raw material for evolution?

Introduces genetic variation necessary for natural selection and adaptation.

New cards
9

Frequency-independent Selections

Directional, Stabilizing, Disruptive, Overdominance, Underdominance

New cards
10

Frequency Dependent Selections

Positive frequency and Negative frequency

New cards
11
How has selection influenced rock pocket mice populations?

Mice with dark fur are favored in lava-covered environments, showing directional selection due to predation pressure.

New cards
12

Positive assortative mating effect on genotypic frequencies?

Increases homozygosity and decreases heterozygosity.

New cards
13

Negative assortative mating effect on genotypic frequencies?

Increases heterozygosity, favoring mating between genetically different individuals.

New cards
14

Inbreeding relation to positive assortative mating?

Inbreeding is a type of positive assortative mating where individuals mate with relatives.
New cards
15
Why is inbreeding depression a conservation concern?

Reduces genetic diversity, leading to lower fitness and increased disease susceptibility.

New cards
16
How does migration affect genetic variation?
Within a population: Increases genetic diversity; Between populations: Can homogenize allele frequencies over time.
New cards
17
Explain the continent-island model of migration.

A large population (continent) supplies alleles to a smaller population (island), island allele frequencies converge to continent allele frequencies.

New cards
18
Explain the island model of migration.

Migration occurs between multiple small populations, leading to convergence on mean of all islands allele frequencies.

New cards
19
How does genetic drift affect allele frequencies?

Causes random changes, potentially leading to allele fixation or loss, especially in small populations.

New cards
20
How are the founder effect and bottleneck effect related to genetic drift?
Both involve small population sizes, leading to random shifts in allele frequencies.
New cards
21
How is genetic drift different from natural selection?
Genetic drift involves random changes in allele frequencies, while natural selection involves non-random changes where beneficial alleles increase in frequency.
New cards
22

Example of genetic drift in a real-world population.

The cheetah population experienced a genetic bottleneck, leading to low genetic diversity.
New cards
23
Give an example of natural selection in action.
Peppered moths changed in frequency based on pollution levels affecting tree bark color.
New cards
24

Three ingredients for Natural Selection

Variation, trait heritability, selective reproductive success

New cards
25

Directional Selection

One allele is favored, leading to allele fixation (one replaces all)

New cards
26

Stabilizing Selection

Intermediate phenotypes are more fit than extreme ones, less diversity

New cards
27

Disruptive Selection

Two or more extreme phenotypes more fit than intermediate; more diversity

New cards
28

Overdominance Selection

heterozygote advantage; higher fitness

New cards
29

Underdominance Selection

heterozygote disadvantage; lower fitness

New cards
30

Positive Frequency Dependent Selection

phenotype fitness increases as more common

New cards
31

Negative Frequency Dependent Selection

phenotype fitness decreases as more common

New cards

Explore top notes

note Note
studied byStudied by 98 people
693 days ago
5.0(4)
note Note
studied byStudied by 241 people
678 days ago
5.0(2)
note Note
studied byStudied by 13 people
833 days ago
5.0(1)
note Note
studied byStudied by 52 people
787 days ago
5.0(1)
note Note
studied byStudied by 33 people
425 days ago
5.0(1)
note Note
studied byStudied by 9 people
169 days ago
5.0(2)
note Note
studied byStudied by 41 people
709 days ago
5.0(1)
note Note
studied byStudied by 100 people
760 days ago
5.0(2)

Explore top flashcards

flashcards Flashcard (112)
studied byStudied by 55 people
302 days ago
5.0(2)
flashcards Flashcard (198)
studied byStudied by 1 person
182 days ago
5.0(1)
flashcards Flashcard (24)
studied byStudied by 34 people
759 days ago
5.0(1)
flashcards Flashcard (47)
studied byStudied by 1 person
39 days ago
5.0(1)
flashcards Flashcard (137)
studied byStudied by 301 people
567 days ago
4.5(4)
flashcards Flashcard (308)
studied byStudied by 7 people
832 days ago
5.0(1)
flashcards Flashcard (35)
studied byStudied by 2 people
303 days ago
5.0(1)
flashcards Flashcard (334)
studied byStudied by 88 people
23 days ago
5.0(2)
robot