Unit 2 Exam

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

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  when there is extensive gene flow within a single species.

A  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.

B  is called the theory of phyletic gradualism.

C  one possible explanation of speciation accepted by biologists today.

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

A  gradualism.

B  microevolution.

C  parallel evolution.

D  punctuated equilibrium.

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

B  natural selection is a powerful process.

C  new mutations are usually maladaptive.

D  environments change slowly.

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

B  genetic drift within populations.

C  sexual selection between two different species

D  gene flow among members of the same species.

A  adaptive radiation.

B  generalization.

C  homology.

D  parallel evolution.

A  extinction

B  migration

C  sympatric speciation.

D  allopatric speciation.

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

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

C  small scale evolutionary changes within a single generation

D  large scale evolutionary change such as speciation

A  evolutionary change within a species.

B  the extinction of a species.

C  the death of individuals in a group.

D  the formation of new species.

A  the appearance of new species

B  any type of genetic mutation

C  the change from one species to another in one generation

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

A  mutation

B  All of these forces may disrupt equilibrium.

C  gene flow

D  genetic drift

A  the exchange of genes between populations

B  the chance loss of alleles in a population

C  the differential reproductive success of individuals

D  the production of new genetic material

A  maladaptive changes in gene frequencies.

B  equilibrium in genetic frequencies.

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

D  adaptive changes in gene frequencies.

A  small populations.

B  medium-sized populations.

C  populations out of equilibrium.

D  large populations.

A  mutation

B  migration

C  genetic drift

D  recombination

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

B  are affected by genes at many loci.

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  mutation

B  migration

C  natural selection

D  genetic drift

A  New variation is slowly added by mutation.

B  Mutations can be hidden in the heterozygous genotype.

C  There is no blending during sexual reproduction.

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

A  were discovered by Darwin.

B  the sex cells or eggs and sperm.

C  do not differ between male and female animals.

D  the somatic cells of the body.

A  genetic drift

B  gene

C  mutation

D  allele

A  Chromosomes come in pairs.

B  These are all true about choromsomes

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

D  Hereditary material is contained in the chromosomes.

A  dominant trait

B  non-genetic trait

C  mendelian trait

D  polygenic 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  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 high juvenile mortality

B  changed over time because of environmental change

C  never changed because of stasis

D  changed because equilibrium existed in the population

A  disruptive selection

B  directional selection

C  stabilizing selection

D  averaging selection

A  almost always occur by chance alone.

B  cannot be passed from parent to offspring.

C  allow organisms to evolve more rapidly.

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

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

B  traits are not inherited by offspring.

C  evolutionary change would proceed in a nonadaptive direction.

D  there is no competition.

A  the struggle for existance.

B  the inheritance of variation.

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

D  variation in fitness.

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.