Test 2 Flashcards
Populations with no selection, mutation, or drift are not ____.
evolving
If a population is not evolving, then frequencies of both the alleles in the population and the genotypes of individuals should remain ____.
fixed
p + q =
1
p^2 + 2pq + q^2 =
1
5 Assumptions of H-W Equilibrium Principle
- No selection
- No mutation
- No gene flow (immigration/emigration)
- No chance
- Mating is random
True or False: Of all the assumptions of the Hardy-Weinberg principle, the one that is most likely to be met in the biological world as a whole isolation with lack of gene flow.
True
True or False: It is possible to have a gene that is beneficial in a population become less frequent from one generation to the next.
True
True or False: It is possible for a trait to have both high heritability and noticeable environmental influences.
False
True or False: Both mutation and (random) sexual reproduction could be viewed as drift events.
True
True or False: Apline Skypilots, due to the harsher conditions, are typically slightly smaller on the tundra above treeline than they are below treeline.
False
_____dominance is the selective advantage of heterozygous individuals in a population.
Over
Drift tends to ____ the levels of heterozygosity in a population.
decrease
_____ _______ is the phenomenon which reduces linkage disequilibrium, which explains why sexual reproduction is useful in this situation.
Genetic recombination
For an asexually reproducing organism, _____ could be considered the main source of variation.
mutation
Codon ____ is the phenomenon exhibit where a specific codon for an amino acid with many possible codons is selected for in highly transcribed genes.
bias
Genetic drift (decreases/increases) variation within a population.
decreases
Stabilizing selection (decreases/increases) variation within a population.
decreases
Directional selection (decreases/increases) variation within a population.
decreases
Isolation (decreases/increases) variation within a population.
decreases
Bottleneck (decreases/increases) variation within a population.
decreases
Homozygote advantage (decreases/increases) variation within a population.
decreases
Self-fertilization (decreases/increases) variation within a population.
decreases
Disruptive selection (decreases/increases) variation within a population.
increases
Frequency-dependent selection (decreases/increases) variation within a population.
increases
Mutation (decreases/increases) variation within a population.
increases
Immigration (decreases/increases) variation within a population.
increases
Does drift typically work in opposition to or reinforce the phenomenon. If either, explain.
Either. It works in opposition if the drift increases variation and reinforces if drift reduces the variation.
Does immigration typically work in opposition to or reinforce the phenomenon. If either, explain.
opposition
Does mutation typically work in opposition to or reinforce the phenomenon. If either, explain.
Either. Opposition if the mutation is not beneficial. Reinforces if the mutation is beneficial.
Does mutation typically work in opposition to or reinforce the phenomenon. If either, explain.
Either. Opposition if the mutation is not beneficial. Reinforces if the mutation is beneficial.
Does mate choice typically work in opposition to or reinforce the phenomenon. If either, explain.
reinforces
Why are non-banded water snakes found on the islands in Lake Erie. Explain why there are some banded forms found on the same islands.
The islands have plain rocks for the sakes to get sun on. The non-banded snakes are hidden from predators. Banded snakes are still seen because they are able migrate into the islands despite the predation when they are on the rocks.
What are the two components of fitness?
Survival to reproduction age and reproduction once getting to reproduction age.
selection pressures are …….
anything that can change the fitness of a phenotype in a population (weather, food, water, mates, shelter, etc.)
Overdominance is selective advantage for (homo-/hetero-)zygotes
hetero
Homozygous advantage is known as
underdominance
