AP BIOLOGY

Detailed explanation-1: -Beneficial Mutations Some mutations have a positive effect on the organism in which they occur. They are calledbeneficial mutations. They lead to new versions of proteins that help organisms adapt to changes in their environment. Beneficial mutations are essential for evolution to occur.

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: -Most mutations are not harmful, but some can be. A harmful mutation can result in a genetic disorder or even cancer. Another kind of mutation is a chromosomal mutation. Chromosomes, located in the cell nucleus, are tiny threadlike structures that carry genes.

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.