Final answer:
A heritable change in genetic material is known as a mutation, which can alter the DNA sequence and potentially lead to changes in proteins and the resulting phenotype. Mutations are significant because they are the source of new genetic material and variation that contributes to evolution and adaptation.
Step-by-step explanation:
A heritable change in genetic material is known as a mutation.
Mutations are changes in the DNA sequence that can be passed down through generations. They may stem from a variety of causes, including errors during DNA replication, exposure to certain environmental factors like radiation or chemicals, or could occur spontaneously. When a mutation affects the sequence of nucleotides in the DNA, it can change how genes are expressed, potentially altering the amino acid sequence of proteins during the process of translation. This, in turn, can have a significant impact on an organism's phenotype. Proteins are crucial as they play a central role in most cellular functions; therefore, mutations can lead to changes in cell and organismal function.
It is through such genetic differences that evolution occurs, as mutations introduce new genetic material into a population. This can lead to adaptation, where traits that aid in an organism's survival and reproduction become more common over time. Mutations can be beneficial, harmful, or neutral, depending on their effect on the organism's fitness in its environment.