Unit 2 Exam

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

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

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

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

A  one possible explanation of speciation accepted by biologists today.

B  is called the theory of phyletic gradualism.

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  gradualism.

B  parallel evolution.

C  punctuated equilibrium.

D  microevolution.

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

B  new mutations are usually maladaptive.

C  natural selection is a powerful process.

D  environments change slowly.

A  gene flow among members of the same species.

B  sexual selection between two different species

C  genetic drift within populations.

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

A  homology.

B  generalization.

C  parallel evolution.

D  adaptive radiation.

A  extinction

B  allopatric speciation.

C  migration

D  sympatric speciation.

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

B  small scale evolutionary changes within a single generation

C  large scale evolutionary change such as speciation

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

A  the formation of new species.

B  the death of individuals in a group.

C  the extinction of a species.

D  evolutionary change within 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  gene flow

D  All of these forces may disrupt equilibrium.

A  the differential reproductive success of individuals

B  the exchange of genes between populations

C  the production of new genetic material

D  the chance loss of alleles in a population

A  equilibrium in genetic frequencies.

B  adaptive changes in gene frequencies.

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

D  maladaptive changes in gene frequencies.

A  small populations.

B  medium-sized populations.

C  large populations.

D  populations out of equilibrium.

A  recombination

B  mutation

C  migration

D  genetic drift

A  are affected by genes at many loci.

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

C  all of these are important in shaping continuously varying traits

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

A  natural selection

B  mutation

C  genetic drift

D  migration

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

B  Mutations can be hidden in the heterozygous genotype.

C  There is no blending during sexual reproduction.

D  New variation is slowly added by mutation.

A  the somatic cells of the body.

B  the sex cells or eggs and sperm.

C  do not differ between male and female animals.

D  were discovered by Darwin.

A  genetic drift

B  gene

C  mutation

D  allele

A  Chromosomes come in pairs.

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

C  Hereditary material is contained in the chromosomes.

D  These are all true about choromsomes

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

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

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

A  never changed because of high juvenile mortality

B  changed over time because of environmental change

C  changed because equilibrium existed in the population

D  never changed because of stasis

A  stabilizing selection

B  directional selection

C  disruptive selection

D  averaging selection

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

B  allow organisms to evolve more rapidly.

C  almost always occur by chance alone.

D  cannot be passed from parent to offspring.

A  traits are not inherited by offspring.

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  there is no competition.

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

B  the inheritance of variation.

C  variation in fitness.

D  the struggle for existance.

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

B  all of these are essential elements of natural selection.

C  individuals within a population vary.

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