AP BIOLOGY

Detailed explanation-1: -A single mutation can have a large effect, but in many cases, evolutionary change is based on the accumulation of many mutations with small effects. Mutational effects can be beneficial, harmful, or neutral, depending on their context or location. Most non-neutral mutations are deleterious.

Detailed explanation-2: -No; only a small percentage of variants cause genetic disorders-most have no impact on health or development. For example, some variants alter a gene’s DNA sequence but do not change the function of the protein made from the gene.

Detailed explanation-3: -Answer and Explanation: “All mutations are harmful and increase the risk of disease such as cancer” is a false statement. It should read “Some mutation may be harmful and increase the risk of diseases such as cancer, but many are beneficial. The majority of mutations are nearly neutral or harmful.

Detailed explanation-4: -The majority of mutations have neither negative nor positive effects on the organism in which they occur. These mutations are called neutral mutations. Examples include silent point mutations. They are neutral because they do not change the amino acids in the proteins they encode.

Detailed explanation-5: -B. Silent mutations are a result of the redundancy (degeneracy) of the genetic code: This is false, as silent mutations are the result of a base substitution that has no discernible effect on the amino acid sequence of a protein.