Which of the Following Statements About Molecular Evolution is True

Question

Which of the following statements about molecular evolution is true?
A)Homologous genes often evolve in the same way.
B)Different regions of the same gene evolve at different rates.
C)Genes in the same organism evolve at about the same rate.
D)Genes in different organisms evolve at about the same rate.
E)Nucleotide substitutions are nonrandom.

Accepted Answer

Different regions of the same gene can be under different selection pressures or exhibit different mutation rates, leading to different rates of evolution.

Answer: A
 Homologous genes, which are descended from a common ancestral gene, often have similar functions and can experience similar evolutionary pressures, leading to similar patterns of evolution.

Answer: E
 While random mutations occur, the fixation of nucleotide substitutions can be influenced by factors such as natural selection, genetic drift, and gene flow, leading to nonrandom patterns of molecular evolution.

Therefore, the correct answer is both B and A.