Two fossil vertebrates, each representing a different class, are found in the undisturbed rock layers of a cliff. One fossil is a representative of the earliest amphibians. The other fossil, found in an older rock layer below the amphibian, is most likely to be

If a segment of DNA is 5′-TAC GAT TAG-3′, the RNA that results from the transcription of this segment will be

If a segment of DNA is 5′-TAC GAT TAG-3′, the RNA that results from the transcription of this segment will be

Assembles ribosomal precursors

Which of the following statements best summarizes organic evolution as it is viewed by modern evolutionists?

Which of the following statements best summarizes organic evolution as it is viewed by modern evolutionists?

A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 49 percent of the animals display a recessive trait (bb), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants. What is the most reasonable conclusion that can be drawn from the fact that the frequency of allele b has not changed over time?

Which of the following best describes an intimate ecological association in which an organism benefits from living on or within a host, but which generally has a negative effect on that host?

This biome can be recognized by its coniferous forests and relatively infertile, acidic soil.

Contains hydrolytic enzymes associated with the intracellular digestion of macromolecules