What do you understand about DNA, gene and chromosome in short?

Explanation

Deoxy ribonucleic acid [DNA] is the material located in the cells and nucleus, that makes up the chromosomes and genes. It.s molecule is in the shape of double helix.
A gene is a segment of DNA that is passed down from parents to children and confers a trait to the offspring. Genes are organised and packaged in units called chromosomes.
Chromosomes are thin, long thread like structure, contains two identical strands, called chromatids, held together by centromere. Humans have 23 pairs of chromosomes.