AP BIOLOGY

Detailed explanation-1: -Mutational effects can be beneficial, harmful, or neutral, depending on their context or location. Most non-neutral mutations are deleterious. In general, the more base pairs that are affected by a mutation, the larger the effect of the mutation, and the larger the mutation’s probability of being 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: -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-4: -Answer and Explanation: The correct answer to this question is B. They always cause a change to an organism’s genotype. Regardless of the cause of the change, a DNA sequence is always altered when it mutates.

Detailed explanation-5: -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.