The first fish:a
were small and jawless but had bony armor.
b. appeared about 2 billion years ago.
c. were the lobe-finned fish.
d. appeared in the Silurian period.
e. developed in the Precambrian period.
A
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Although inbreeding by itself does not affect allele frequencies, how might inbreeding indirectly affect allele frequencies over the course of many generations if natural selection was also occurring?
A. Inbreeding favors homozygotes. If a homozygote has a higher Darwinian fitness, inbreeding would accelerate the prevalence of the allele in the population. If a homozygote has a lower fitness, inbreeding would accelerate the elimination of the allele from the population. B. Inbreeding favors homozygotes. If a homozygote has a lower Darwinian fitness, inbreeding would accelerate the prevalence of the allele in the population. If a homozygote has a higher fitness, inbreeding would accelerate the elimination of the allele from the population. C. Inbreeding never occurs in a natural population, therefore the fitness and allele frequencies would not be affected. D. None of these choices are correct.
Hydrostatic skeletons are normally used for movement by all of the following animals EXCEPT
A. annelids. B. cnidarians. C. crustaceans. D. nematodes. E. earthworms.
The __________ governs expression of three genes active in lactose metabolism. Fill in the blank(s) with the appropriate word(s)
Life first evolved in and the earliest forms of life lived in ________
Fill in the blank(s) with correct word