Unit 2 Exam

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

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

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

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

A  one possible explanation of speciation accepted by biologists today.

B  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.

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

D  is called the theory of phyletic gradualism.

A  gradualism.

B  parallel evolution.

C  microevolution.

D  punctuated equilibrium.

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

B  new mutations are usually maladaptive.

C  environments change slowly.

D  natural selection is a powerful process.

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

B  gene flow among members of the same species.

C  genetic drift within populations.

D  sexual selection between two different species

A  generalization.

B  parallel evolution.

C  homology.

D  adaptive radiation.

A  allopatric speciation.

B  extinction

C  sympatric speciation.

D  migration

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

B  large scale evolutionary change such as speciation

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

D  small scale evolutionary changes within a single generation

A  the extinction of a species.

B  evolutionary change within a species.

C  the death of individuals in a group.

D  the formation of new species.

A  the change from one species to another in one generation

B  the appearance of new species

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

D  any type of genetic mutation

A  All of these forces may disrupt equilibrium.

B  genetic drift

C  gene flow

D  mutation

A  the differential reproductive success of individuals

B  the chance loss of alleles in a population

C  the production of new genetic material

D  the exchange of genes between populations

A  maladaptive changes in gene frequencies.

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

C  equilibrium in genetic frequencies.

D  adaptive changes in gene frequencies.

A  large populations.

B  populations out of equilibrium.

C  small populations.

D  medium-sized populations.

A  genetic drift

B  recombination

C  migration

D  mutation

A  all of these are important in shaping continuously varying traits

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

C  are affected by genes at many loci.

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

A  genetic drift

B  migration

C  natural selection

D  mutation

A  New variation is slowly added by mutation.

B  There is no blending during sexual reproduction.

C  Mutations can be hidden in the heterozygous genotype.

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

A  the somatic cells of the body.

B  the sex cells or eggs and sperm.

C  were discovered by Darwin.

D  do not differ between male and female animals.

A  allele

B  mutation

C  gene

D  genetic drift

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

B  Chromosomes come in pairs.

C  These are all true about choromsomes

D  Hereditary material is contained in the chromosomes.

A  polygenic trait

B  mendelian trait

C  dominant trait

D  non-genetic trait

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

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

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

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

A  changed over time because of environmental change

B  never changed because of high juvenile mortality

C  never changed because of stasis

D  changed because equilibrium existed in the population

A  averaging selection

B  stabilizing selection

C  disruptive selection

D  directional selection

A  allow organisms to evolve more rapidly.

B  almost always occur by chance alone.

C  cannot be passed from parent to offspring.

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

A  there is no competition.

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

C  evolutionary change would proceed in a nonadaptive direction.

D  traits are not inherited by offspring.

A  the inheritance of variation.

B  the struggle for existance.

C  variation in fitness.

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

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

B  individuals within a population vary.

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

D  all of these are essential elements of natural selection.