gene refers to long deoxyribonucleic acid (DNA) molecule, the basic physical unit of heredity that appears as a location on a chromosome.
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Gene is defined as the fundamental physical unit or the basic unit of heredity. A gene is a linear sequence of nucleotides along a segment of DNA (deoxyribonucleic acid) that carries the coded instructions for the synthesis of RNA, which, when translated into protein, leads to hereditary characteristics. Gene is the unit of heredity that maintains its structural identity from one generation to another