Among the three, the gene is the smallest portion, as it is a small sequence of nitrogenous DNA bases. Several sequenced genes form the DNA, which is presented in a condensed structure in a chromosome, that is, it stores the DNA.
The human being has 46 chromosomes: 23 chromosomes of maternal origin and 23 chromosomes of paternal origin. With 44 autosomes and 2 sex chromosomes (“Y” is male and “X” is female).