factors that affect evolution

What is another definition for evolution mentioned in this lecture?

Evolution is a change in the relative frequency of alleles in a population's gene pool.

What are the three ways that mutations can happen in our DNA?

Radiation (X-rays, UV exposure), chemicals (pesticides, herbicides, nicotine), and during DNA replication.

Given a scenario, how do you determine if a mutation is beneficial, harmful, or neutral?

A beneficial mutation positively impacts an organism's ability to survive in its environment, while a harmful mutation negatively impacts that ability.

Do individual organisms evolve, or do populations evolve?

Populations evolve.

What are four factors that will affect the frequency of certain alleles in a population's gene pool?

Natural selection, gene flow, genetic drift, and inbreeding.

If a population's size is significantly reduced (e.g., by a natural disaster), what happens to its gene pool?

By chance, the survivors will have certain alleles that will change the gene pool, resulting in decreased genetic variation in the population.

How does inbreeding increase the chance of expressing a recessive deleterious allele?

Inbreeding is the reproduction of closely related animals over multiple generations, which increases the likelihood of expressing recessive alleles that make an animal "less fit".

How are artificial and natural selection similar?

Both involve selecting for specific traits; however, in artificial selection (selective breeding), humans rather than the environment decide which traits are successful.

What are the advantages of artificial selection?

It tries to establish certain traits that humans find desirable in domesticated species, such as disease resistance, strength, calmness, or meat yield.

What are the disadvantages of artificial selection?

It results in decreased genetic diversity in the population, and undesirable traits from both parents may appear in the offspring.

Define mutations and mutagens.

Mutations are inheritable changes to DNA that occur in germ cells; mutagens are factors like radiation or chemicals that cause these mutations.

Define gene pool and gene flow.

A gene pool consists of all the alleles in all individuals of a population; gene flow is the exchange of alleles between two populations.

Define genetic drift and genetic bottleneck.

Genetic drift is a change in a gene pool due to random chance; a genetic bottleneck is a type of drift where an event like a natural disaster significantly reduces population size.

Define founder effect.

: This happens when a small number of individuals move to a new habitat and start a new population, with the new gene pool depending on the alleles of the founders.

Define inbreeding

Inbreeding is reproduction of closely related animals

deleterious allele

a deleterious allele is a recessive allele that makes an animal "less fit".

Define artificial selection (selective breeding).

When humans, rather than the environment, decide which traits are successful in a population.