AP BIOLOGY

Detailed explanation-1: -Genetic variations can arise from gene variants (also called mutations) or from a normal process in which genetic material is rearranged as a cell is getting ready to divide (known as genetic recombination). Genetic variations that alter gene activity or protein function can introduce different traits in an organism.

Detailed explanation-2: -Mutations are changes in the genetic sequence, and they are a main cause of diversity among organisms. These changes occur at many different levels, and they can have widely differing consequences.

Detailed explanation-3: -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-4: -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.

Detailed explanation-5: -Mutations are the original source of genetic variation. A mutation is a permanent alteration to a DNA sequence. De novo (new) mutations occur when there is an error during DNA replication that is not corrected by DNA repair enzymes.