Unit 17 Biology Test

Match the following

• all the genes, including all the different alleles for each gene, that are present in a population

• Hardy-Weinberg Principle

• situation in which allele frequencies in a population remain the same

• genetic equilibrium

• number of times that an allele occurs in a gene pool

• gene pool

• allele frequencies remain constant unless 1 or more factors cause those frequencies to change

• allele frequency

• uses mutation rates in DNA to estimate the time that 2 species have been evolving indendently

• molecular clock

Match the following

• individuals at upper and lower ends of curve have higher fitness than middle of the curve

• polygenic trait

• trait controlled by two or more genes

• disruptive selection

• form of reproductive isolation in which 2 or more species reproduce at different times

• species

• a change in allele frequency following a dramatic reduction in the size of a population

• bottleneck effect

• a group of similar organisms that can breed and produce fertile offspring

• temporal isolation

Match the following

• 2 populations are separated by geographic barriers leading to the formation of 2 species

• geographic isolation

• change in allele frequencies as a result of the migration of a small subgroup of a population

• genetic drift

• random change in allele frequency that cause an allele to become more or less common in a population

• speciation

• those at one end of the curve have higher fitness than those in the middle or other end of the curve

• directional selection

• formation of a new species

• founder effect

Match the following

• 2 populations develop differences in courtship rituals that prevent them from breeding

• sexual selection

• separation of a species so that they no longer interbreed and evolve into 2 separate species

• behavioral isolation

• trait controlled by one gene that has 2 alleles

• reproductive isolation

• when individuals select mates based on inheritable traits

• stabilizing selection

• individuals near the center of the distribution curve have higher fitness than those at either end

• single-gene trait

Which of the following conditions is MOST likely to result in changes in allele frequencies in a population?

• random mating

• small population size

• no migration into or out of a population

• absence of natural selection

Mutations and the genetic recombination that occurs during sexual reproduction are both sources of

• genetic variation

• stabilizing selection

• genetic equilibrium

• genetic drift

In a population of lizards, the smallest and largest lizards are more easily preyed upon than medium-size lizards. What kind of natural selection is MOST likely to occur in this situation?

• genetic drift

• sexual selection

• stabilizing selection

• directional selection

Populations of antibiotic-resistant bacteria are the result of the process of

• natural selection

• temporal isolation

• genetic drift

• artificial selection

The length of time that two taxa have been evolving separately can be estimated using

• genetic drift

• gene duplication

• molecular clock

• Hox genes

Mutations that improve an individual's ability to survive and reproduce are

• harmful

• neutral

• beneficial

• chromosomal