BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Mutations result either from errors in DNA replication or from the damaging effects of mutagens, such as chemicals and radiation, which react with DNA and change the structures of individual nucleotides. All cells possess DNA-repair enzymes that attempt to minimize the number of mutations that occur (Section 14.2).

Detailed explanation-2: -As such, the nucleotide sequences found within it are subject to change as the result of a phenomenon called mutation. Depending on how a particular mutation modifies an organism’s genetic makeup, it can prove harmless, helpful, or even hurtful.

Detailed explanation-3: -A gene variant is a permanent change in the DNA sequence that makes up a gene. This type of genetic change used to be known as a gene mutation, but because changes in DNA do not always cause disease, it is thought that gene variant is a more accurate term.

Detailed explanation-4: -Mutations can also be the result of the addition of a base, known as an insertion, or the removal of a base, also known as deletion. Sometimes a piece of DNA from one chromosome may get moved to another chromosome or to another region of the same chromosome; this is also known as translocation.

Detailed explanation-5: -Epigenetics is the study of how your behaviors and environment can cause changes that affect the way your genes work. Unlike genetic changes, epigenetic changes are reversible and do not change your DNA sequence, but they can change how your body reads a DNA sequence.