Unit 2 Exam

A  when there is extensive gene flow within a single species.

B  when interbreeding between two different species results in less successful hybrid offspring.

C  males and females don’t like each other very much and so prefer not to mate.

D  because there is over-population and species survival depends on a new species evolving.

A  is called the theory of phyletic gradualism.

B  one possible explanation of speciation accepted by biologists today.

C  one possible explanation of speciation accepted by biologists today, is not the only pattern of speciation observed in the natural world and is called the theory of phyletic gradualism.

D  is not the only pattern of speciation observed in the natural world.

A  parallel evolution.

B  gradualism.

C  punctuated equilibrium.

D  microevolution.

A  new mutations are usually maladaptive.

B  gene flow between individuals within the population keeps them similar to each other.

C  environments change slowly.

D  natural selection is a powerful process.

A  sexual selection between two different species

B  they way natural selection favors particular traits suited to a specific ecological niche.

C  gene flow among members of the same species.

D  genetic drift within populations.

A  adaptive radiation.

B  generalization.

C  parallel evolution.

D  homology.

A  migration

B  sympatric speciation.

C  allopatric speciation.

D  extinction

A  how the evolution of one species affects the evolution of another species

B  large scale evolutionary change such as speciation

C  small scale evolutionary changes within a single generation

D  the relationship between humans and other animals in their ecological niche

A  the death of individuals in a group.

B  evolutionary change within a species.

C  the formation of new species.

D  the extinction of a species.

A  the change from one species to another in one generation

B  the change in allele frequencies from one generation to the next

C  any type of genetic mutation

D  the appearance of new species

A  genetic drift

B  mutation

C  All of these forces may disrupt equilibrium.

D  gene flow

A  the chance loss of alleles in a population

B  the exchange of genes between populations

C  the production of new genetic material

D  the differential reproductive success of individuals

A  equilibrium in genetic frequencies.

B  maladaptive changes in gene frequencies.

C  changes in gene frequencies that are random with respect to adaptation.

D  adaptive changes in gene frequencies.

A  medium-sized populations.

B  small populations.

C  populations out of equilibrium.

D  large populations.

A  recombination

B  mutation

C  genetic drift

D  migration

A  are affected by genes at many loci.

B  all of these are important in shaping continuously varying traits

C  can be greatly impacted by the environment during an individual’s growth and development.

D  are shaped by many genes, each with only a small effect on the phenotype.

A  migration

B  mutation

C  natural selection

D  genetic drift

A  All of these are ways that genetic variation remains within a population.

B  New variation is slowly added by mutation.

C  Mutations can be hidden in the heterozygous genotype.

D  There is no blending during sexual reproduction.

A  do not differ between male and female animals.

B  were discovered by Darwin.

C  the somatic cells of the body.

D  the sex cells or eggs and sperm.

A  allele

B  gene

C  mutation

D  genetic drift

A  These are all true about choromsomes

B  Chromosomes come in pairs.

C  Hereditary material is contained in the chromosomes.

D  One chromosome from each homologous pair is passed on to gametic cells during meiosis.

A  mendelian trait

B  polygenic trait

C  dominant trait

D  non-genetic trait

A  a large number of the birds had died as a result of the drought

B  the survivors of the drought had a larger average beak size

C  The Grants found all these things as part of their study.

D  beak size is inherited so the next generation had a larger average beak size

A  never changed because of stasis

B  never changed because of high juvenile mortality

C  changed because equilibrium existed in the population

D  changed over time because of environmental change

A  directional selection

B  disruptive selection

C  stabilizing selection

D  averaging selection

A  allow organisms to evolve more rapidly.

B  are components of organisms that enable them to survive and reproduce.

C  cannot be passed from parent to offspring.

D  almost always occur by chance alone.

A  traits are not inherited by offspring.

B  there are no differences in the traits to be favored and affect survival and reproducation.

C  there is no competition.

D  evolutionary change would proceed in a nonadaptive direction.

A  Natural selection is based on all three of these answers.

B  variation in fitness.

C  the inheritance of variation.

D  the struggle for existance.

A  all of these are essential elements of natural selection.

B  individuals within a population vary.

C  individuals with useful adaptations will be more likely to survive and reproduce.

D  while organisms within a population reproduce rapidly, resources are limited.