What are mutations?

Mutations are defined as changes in the DNA sequence. These alterations can occur in various forms, such as substitutions, insertions, deletions, or duplications of nucleotide bases in the genetic material. Mutations can arise due to mistakes during DNA replication, exposure to certain chemicals or radiation, or can be inherited from previous generations.

The significance of mutations lies in their potential to affect an organism's traits, development, and evolutionary processes. Some mutations can have no effect or be neutral, while others may lead to changes in the function of proteins synthesized from that DNA, which can sometimes be advantageous, detrimental, or have no observable effect.

The other choices describe different biological processes or concepts that do not accurately represent mutations. Cellular respiration refers to the metabolic processes that convert glucose into usable energy, infections involve pathogens that affect living organisms, and normal variations in traits typically refer to heritable physical characteristics rather than changes at the DNA sequence level. Thus, understanding mutations is essential in fields such as genetics, biology, evolution, and medicine.