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.

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  punctuated equilibrium.

B  microevolution.

C  parallel evolution.

D  gradualism.

A  environments change slowly.

B  natural selection is a powerful process.

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

D  new mutations are usually maladaptive.

A  genetic drift within populations.

B  sexual selection between two different species

C  gene flow among members of the same species.

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

A  parallel evolution.

B  homology.

C  adaptive radiation.

D  generalization.

A  sympatric speciation.

B  extinction

C  allopatric speciation.

D  migration

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  large scale evolutionary change such as speciation

D  small scale evolutionary changes within a single generation

A  the formation of new species.

B  evolutionary change within a species.

C  the extinction of a species.

D  the death of individuals in a group.

A  the appearance of new species

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

C  any type of genetic mutation

D  the change from one species to another in one generation

A  gene flow

B  genetic drift

C  All of these forces may disrupt equilibrium.

D  mutation

A  the production of new genetic material

B  the chance loss of alleles in a population

C  the differential reproductive success of individuals

D  the exchange of genes between populations

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  small populations.

B  large populations.

C  medium-sized populations.

D  populations out of equilibrium.

A  genetic drift

B  recombination

C  mutation

D  migration

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

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

C  are affected by genes at many loci.

D  all of these are important in shaping continuously varying traits

A  mutation

B  natural selection

C  migration

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  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  gene

B  mutation

C  genetic drift

D  allele

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  non-genetic trait

B  dominant trait

C  polygenic trait

D  mendelian 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 stasis

B  changed because equilibrium existed in the population

C  never changed because of high juvenile mortality

D  changed over time because of environmental change

A  stabilizing selection

B  disruptive selection

C  averaging selection

D  directional selection

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

B  cannot be passed from parent to offspring.

C  almost always occur by chance alone.

D  allow organisms to evolve more rapidly.

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

B  there is no competition.

C  evolutionary change would proceed in a nonadaptive direction.

D  traits are not inherited by offspring.

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

B  all of these are essential elements of natural selection.

C  individuals within a population vary.

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