Which of the following statements about nonsynonymous substitutions is true?
A) They always affect the protein's shape and charge.
B) They occasionally confer a selective advantage to the organism.
C) The rate of their evolution is roughly the same among different genes.
D) They are unlikely to be influenced by natural selection.
E) All of the above

Question

Quizplus · Accepted Answer

Nonsynonymous substitutions, also known as missense mutations, change the amino acid sequence of a protein, which can potentially affect its function. These substitutions can occasionally confer a selective advantage to the organism, such as increased resistance to a particular environmental stress or improved enzymatic activity. However, the rate of evolution for nonsynonymous substitutions can vary widely among different genes, depending on factors such as the degree of conservation of the protein's function and the strength of purifying selection. It is not necessarily true that these substitutions always affect the protein's shape and charge, nor is it true that they are unlikely to be influenced by natural selection.

Which of the Following Statements About Nonsynonymous Substitutions Is True