Bio 103 Quiz 2

What is true of microevolution? a) It is evolution that results in the origin of small numbers of new species. b) It is evolution that involves only tiny changes to DNA, such as point mutations, producing only small (if any) changes to phenotype. c) It is evolution that is restricted to individual organisms. d) It is the kind of evolution that can change the relative abundance of a particular allele in a gene pool over the course of generations. e) It is evolution that influences only a small subset of the populations that comprise a species.

The original source of all genetic variation is _____. a) recombination b) natural selection c) sexual reproduction d) independent assortment e) mutation

One of the following is NOT a source of genetic variation. a) rapid reproduction b) mutation c) alteration of gene number or position d) genetic drift e) sexual reproduction

According to the Hardy-Weinberg theorem, the frequencies of alleles in a population will remain constant if _____ is the only process that affects the gene pool. a) sexual selection b) sexual reproduction c) mutation d) genetic drift e) immigration

The evolutionary effects of genetic drift are greatest when _____. a) sexual selection occurs b) intraspecific competition is weak c) the population size is small d) intraspecific competition is intense e) the population size is large

What situation most likely explains the occasional high frequency of certain inherited disorders among human populations established by a small population? a) gene flow b) bottleneck effect c) mutation d) founder effect e) nucleotide variability

In evolutionary terms, an organism's fitness is measured by its _____. a) health b) stability in the face of environmental change c) genetic variability d) contribution to the gene pool of the next generation e) mutation rate

Blue poppies native to China were grown at a plant-breeding center in California. The plants with the thickest leaves were most likely to survive and reproduce in the drier climate. After several generations, the percentage of thick-leaved plants had increased by 42%. This adaptation of the poppies to their new environment is due to _____. a) neutral variation b) stabilizing selection c) disruptive selection d) genetic drift e) directional selection

What is the only evolutionary mechanism that consistently leads to adaptive evolution? a) the bottleneck effect b) natural selection c) gene flow d) neutral variation e) genetic drift

How does diploidy help to preserve genetic variation? a) It allows recessive alleles that may not be favored in the current environment to be preserved in the gene pool by propagation in heterozygotes. b) It allows the frequency of a recessive allele in a population to be predicted under certain conditions. c) It helps individual organisms make a greater contribution to the gene pool of the next generation. d) It restricts the gene pool by chance events such as floods or other catastrophic events. e) It fosters the exchange of genes between different populations.

What is the most important factor that holds a gene pool of a species together and prevents speciation? a) behavioral isolation b) sexual selection c) gene flow d) prezygotic barriers e) hybridization

Two animals are considered members of different species if they _____. a) are geographically isolated b) live in different habitats c) cannot mate and produce viable, fertile offspring d) are members of different populations e) look different

According to the phylogenetic species concept, what is a species? a) a population with a distinct fossil record b) a clone of genetically identical organisms c) a set of organisms with a unique genetic history d) a population that interbreeds and produces fertile offspring e) a population that is physically able to mate even if there are no offspring or the offspring are infertile

Which of these is an example of temporal isolation? a) One species performs a specific courtship dance. the other species does not. b) One species is nocturnal, and the other species is not. c) The average weight of the individuals in one species is 45 kg; in the other species the average is 290 kg. d) One species is found only in New York, the other only in London. e) One is a type of primate, the other is a type of marsupial.

Which of the following is the first step in allopatric speciation? a) polyploidy b) hybridization c) formation of a reproductive barrier d) geographic isolation e) genetic drift

Sympatric speciation is _____. a) the emergence of many species from a single ancestor b) the appearance of a new species in the same area as the parent population c) especially important in the evolution of island species d) the process by which most animal species have evolved e) initiated by the appearance of a geographic barrier

Hybrid zones provide an opportunity to investigate _____. a) mutations b) the evolution of reproductive isolation c) allopatric speciation d) polyploidy e) punctuated equilibrium

A certain species of salamander was split into two populations by a wide, dry valley, and the populations began to diverge from each other. After a period of time, some members of the two populations began to interbreed in a hybrid zone at the southern end of the valley. Only weak reproductive barriers existed by this time, so the two populations could freely interbreed and re-establish gene flow. This outcome in a hybrid zone is known as _____. a) punctuated equilibrium b) fusion c) speciation d) reinforcement e) stability

According to the _____ model, evolution occurs in spurts; species evolve relatively rapidly then remain unchanged for long periods. a) geographic isolation b) adaptive radiation c) punctuated equilibrium d) nondisjunction e) gradualist

Which of the following has been shown to cause speciation most rapidly? a) hybridization b) differential resource exploitation c) sexual selection d) autopolyploidy e) punctuated equilibrium

What is a homologous structure?

What is an analogous structure?

What is a vestigial structure?

What is convergent evolution?

What type of structures are because of convergent evolution?

What makes evolution possible?

What is microevolution?

What does hardy weinberg equilibrium test?

What is neutral variation?

What is the definition of a population?

What is the equation for genotypic hardy weinberg equilibrium?

What is the equation for phenotypic hardy weinberg equilibrium?

What are the 5 conditions for hardy weinberg equilibrium?

Name three things that can alter allele frequencies in a population?

What is adaptive evolution?

Name two types of genetic drift

What is genetic drift?

In what type of community is genetic drift most influential?

What is the founder effect?

What is the bottleneck effect?

What is gene flow?

What is the only mechanism that consistently causes adaptive evolution?

What is relative fitness?

What is directional selection

What is disruptive selection

What is stabilizing selection

What does balancing selection favor?

What does frequency dependent selection depend on?

What is speciation?

What is macroevolution

What does the biological species concept define a species as?

What is reproductive isolation?

What is the difference between allopatric and sympatric speciation?

What is punctuated equilibria?

What are adaptive radiations?

How does genetic drift affect genetic variation