Exam 15: Processes of Evolution

A) the rate of molecular mutation is influenced by natural selection.
B) most variability in the structure of molecules does not affect their functioning.
C) closely related species have more similar molecular structures than do distantly related species.
D) organisms evolved through neutral changes in their molecules.
E) mutations neither add nor subtract amino acids from molecules.

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A) Species with larger population sizes have more noncoding DNA.
B) Species with smaller population sizes have more noncoding DNA.
C) Species with larger genomes lose DNA more slowly through mutational processes than those with smaller genomes.
D) Species with larger genomes lose DNA more quickly through mutational processes than those with smaller genomes.
E) There is an inverse relationship between the total amount of DNA in the genome and the percentage of the DNA that is noncoding.

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A) an application of Muller's ratchet.
B) bioprospecting.
C) bioremediation.
D) bioinfomatics.
E) an application of the principles of convergent evolution.

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A) Most populations have little genetic variation.
B) Natural selection is typically a stabilizing phenomenon.
C) Directional selection is commonplace.
D) Genetic drift counters the effects of selection,particularly in large populations.
E) Mutation rates are very high.

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A) Two different populations can have the same allele frequencies but different genotype frequencies.
B) Populations that are polymorphic have only one allele at a locus.
C) If an allele is fixed in a population,that population is polymorphic.
D) Allelic frequencies are measures of how a population's genetic variation is distributed among its members.
E) A population that is monomorphic has a great deal of genetic variation.

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A) breaks down combinations of beneficial alleles.
B) leads to Muller's ratchet.
C) hampers DNA repair.
D) permits the elimination of deleterious mutations.
E) decreases genetic variation.

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A) silent
B) missense
C) disruptive
D) neutral
E) beneficial

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A) Stabilizing selection
B) Genetic drift
C) Sexual selection
D) Disruptive selection
E) Gene flow

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A) Only trial 1 shows heterozygote advantage.
B) Only trial 2 shows heterozygote advantage.
C) Both trials 1 and 2 show heterozygote advantage.
D) Only trial 3 shows heterozygote advantage.
E) No trial shows heterozygote advantage.

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A) Very low levels of genetic variation
B) Very few heterozygous individuals
C) Allele frequencies different from those of historical populations
D) Considerable genetic polymorphism
E) Genotypic frequencies different from those of historical populations

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A) breaking down of adaptive combinations of genes by recombination.
B) elimination of deleterious mutations due to sexual reproduction.
C) accumulation of deleterious mutations in asexual lineages.
D) crossing over and independent assortment of chromosomes during meiosis.
E) maintenance of genetic variation via disruptive selection.

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A) 1.2
B) 12
C) 200,000
D) 1 million
E) 2.4 million

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A) perform foregut fermentation.
B) carry oxygen in the blood.
C) defend the body from bacteria.
D) assist in thermoregulation.
E) maintain a stable pH.

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A) steadily increases
B) increases to a point,and then levels off
C) stays more or less the same
D) increases at first,and then declines
E) steadily decreases

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A) A plant population that is very resistant to drought due to the action of natural selection
B) The process by which a plant population became drought resistant
C) The increased ability (above baseline) of an individual plant to withstand further drought after it has received a heat shock,which causes the expression of specific proteins that enable more efficient use of water
D) A zebra that runs quickly to evade lions
E) A lion that runs quickly in order to catch zebra prey

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A) Stabilizing selection
B) Directional selection
C) Positive selection
D) Disruptive selection
E) Purifying selection

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A) ¹/₉
B) ¹/₅
C) ¹/₃
D) ⁴/₅
E) ⁸/₉

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