BIOL 320 FINAL EXAM NEWEST 2025 ACTUAL EXAM
2025/2026 NEWEST ACTUAL EXAM WITH COMPLETE
QUESTIONS AND VERIFIED ANSWERS |ALREADY GRADED
A+|
When selection favors heterozygous genotypes over homozygous
genotypes (i.e., heterozygote advantage) ... - ANSWER-the
selective advantage enjoyed by the deleterious allele in
heterozygotes balances/offsets the selective disadvantage
suffered by homozygous recessive individuals.
there recessive allele is maintained at a frequency greater than
that predicted by Hardy-Weinberg principles based on the
strength of selection against the recessive allele.
genetic diversity in the population can be maintained, in spite of
selection acting against the recessive allele.
Which of the following can maintain deleterious alleles in a
population at higher-than-expected frequencies? - ANSWER-
migration
mutation
genetic drift
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Many small, isolated populations demonstrate high incidences of
autosomal recessive disorders. Which mechanisms best
explains/creates this situation: - ANSWER-Genetic Drift
Inbreeding (Non-random mating)
_______ theory proposes that advantageous mutations are very
rare and that most alleles of genes are selectively _______. The
rate of substitution for most genes will therefore be _______ to
the neutral mutation rate. - ANSWER-neutral
neutral
equal
_______ theory proposes that advantageous mutations are
common enough that they must be taken into account. As such,
the rate of substitution will reflect the action of natural selection on
_______ alleles. - ANSWER-selectionist
advantageous
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In small, relictual populations of organisms, such as the Lesser
Pahoa Kipuka Chicken, evidence that genetic drift had been
acting on the individual populations would include which of the
following? - ANSWER-Individual populations would be fixed for a
single genotype, but genotypes would vary among populations.
Average heterozygosity (% of heterozygotes) would be very low
or absent in all populations.
Which of the mechanisms of evolution is adaptive (i.e.,
consistently adapts the population to the environment by
increasing the frequency of advantageous alleles)? - ANSWER-
Natural Selection
Which mechanism does not have the potential to change allele
frequencies within a population from one generation to the next? -
ANSWER-non-random mating
Inbreeding increases the frequency of _______ genotypes in a
population, and reduces the frequency of _______ genotypes. -
ANSWER-homozygous
heterozygous