Reference no: EM133458448
Questions
1. A small group of individuals who colonize a new area most likely will not represent a random sample of alleles of the population from which they came. This is the concept of:
• genetic drift
• founder's effect
• assortative mating
• nonrandom mating
2. Gene flow refers to:
• the movement of organisms to new areas, but only if they don't mate with the local population
• the separation of groups by geographic barriers.
• the movement of alleles from one gene pool into another gene pool, transmitted as individuals migrate or visit new areas.
• when a gene gradually shifts from one position on a chromosome to another
3. Genetic equilibrium is maintained in a gene pool under ideal conditions.
This equilibrium can be disturbed by:
• All of these forces may disrupt equilibrium.
• gene flow
• genetic drift
• mutation
4. The hemoglobin S allele increased in frequency in West African populations due to which of the following?
• increased mutation rates
• genetic drift
• natural selection
• migration
5. If a population is in genetic equilibrium, the frequency of alleles will:
• show an increase in recessive alleles
• change only slightly
• remain constant
• show an increase in dominant alleles
6. Evolution can be technically defined as
• the change from one species to another in one generation
• the change in allele frequencies from one generation to the next
• the appearance of new species
• any type of genetic mutation
7. Microevolution is:
• the formation of new species.
• evolutionary change within a species.
• the death of individuals.
• the extinction of a species.
8. Allopatric speciation can occur when:
• a geographic barrier causes two subgroups of a population to no longer meet
• a small population of animals is completely wiped out by a volcano
• a large population of animals is completely wiped out by a volcano
• continuous gene flow occurs between two parts of a population
9. Allopatric speciation can occur when:
• a subpopulation is physically separated from the mother population.
• gene flow is interrupted between two subgroups of a mother population.
• lack of gene flow prevents genetic variants from being exchanged between populations.
• All of these can cause allopatric speciation.
10. The rapid expansion and diversification of groups of organisms into newly available ecological niches is termed
• adaptive radiation.
• parallel evolution.
• generalization.
• homology.
11. According to the ecological species concept, a species is a group of organisms:
• that interbreed.
• that are shaped by similar natural selection pressures to survive in a particular niche.
• that live on top of each other.
• that share DNA but not necessarily morphological characteristics.
12. The ecological species concept emphasizes that species can be defined by:
• the presence of genetic mutations.
• the lack of gene flow between species.
• the presence of gene flow within species.
• the active work of natural selection favoring traits, keeping members of the species similar.
13. According to the biological species concept, species remain the same because:
• environments change slowly.
• new mutations are usually maladaptive.
• gene flow between individuals within the population keeps them similar to each other.
• natural selection is a powerful process.
14. According to the ecological species concept, individuals within a species remain similar to each other because:
• lack of gene flow prevents mixing of genes.
• individuals in the same population share DNA.
• individuals in the same environment sometimes experience different selection pressures.
• individuals in the same environment experience similar natural selection pressures
15. The theory that species persist unchanged for long periods and then undergo rapid evolutionary change is known as
• punctuated equilibrium.
• parallel evolution.
• gradualism.
• microevolution.
16. The theory that macroevolution proceeds as the result of gradual microevolutionary change
• is not the only pattern of speciation observed in the natural world.
• is called the theory of phyletic gradualism.
• one possible explanation of speciation accepted by biologists today.
• all of these
17. Reproductive isolating mechanisms may evolve
• males and females don't like each other very much and so prefer not to mate.
• when interbreeding between two different species results in less successful hybrid offspring.
• because there is over-population and species survival depends on a new species evolving.
• when there is extensive gene flow within a single species.
18. Which of the following can result in pre-mating reproductive isolation?
• courtship display
• hybrid sterility
• zygote failure
• pleiotropy