Molecular Evolution and Inbreeding (4)

These flashcards cover the key concepts related to molecular evolution, inbreeding, and genetic mechanisms as discussed in the lecture.

What types of loci are expected to evolve fastest according to the Neutral theory of molecular evolution?

DNA regions without function, synonymous sites, and genes with less vital functions.

What does the inbreeding coefficient (F) range from and what do the endpoints signify?

Ranges from 0 (completely outbred) to 1 (completely inbred).

What is inbreeding depression?

It refers to the reduced biological fitness in a given population due to inbreeding, leading to increased homozygosity.

How is Fst defined in terms of migration?

Fst is a measure of migration that ranges from 0 (complete panmixis) to 1 (no migration).

What is the difference between substitution rate and mutation rate?

Substitution rate refers to the rate at which new mutations become fixed in a population, while mutation rate is the rate at which new mutations occur.

Is the substitution rate influenced by the population size of the species? Why or why not?

Yes, because larger populations can fix mutations more effectively due to greater genetic diversity.

Which portions of the genome accumulate the most substitutions between species? Why?

Non-functional regions accumulate more substitutions due to reduced selection pressure.

What are synonymous and non-synonymous sites? Which accumulates substitutions more rapidly? Why?

Synonymous sites do not change the protein sequence and accumulate substitutions more rapidly than non-synonymous sites, which affect the protein function.

Does non-random mating cause evolution?

Yes, non-random mating can lead to changes in genotype frequencies and may affect evolution.

How does non-random mating affect homozygotes and heterozygotes?

It can increase the frequency of homozygotes and decrease the frequency of heterozygotes.

Define genetic load in context with inbreeding depression.

Genetic load refers to the accumulation of deleterious alleles in a population, which increases during inbreeding depression due to reduced genetic diversity.

What are two ways of estimating inbreeding depression?

Estimation can be done through fitness measures in inbred versus outbred individuals or through trait performance.

What is the coefficient of inbreeding (F)?

It measures the probability that two alleles at a locus in an individual are identical by descent.