A gene is a discrete sequence of DNA (or RNA in some cases) that encodes for a particular sequence of amino acids. These amino acid sequences are put together to form proteins, so a gene is the most basic unit measurement of heredity. A chromosome is a sequence of double helical DNA that is composed of thousands of individual genes. Human cells have 23 pairs of chromosomes. Of these, 1 pair are sex chromosomes and they are denoted by X and Y. Females have 2 X chromosomes and males have 1 X and 1 Y chromosome. Finally, gene linkage is the tendency for genes that are located close to each other on a particular chromosome to be inherited together during cell division.
*Gene is a molecular unit of heredity of a living organism.Chromosome is a DNA molecule package into thread-like structure.
*X Chromosome is one of the two sex chromosome in human.Female have two X chromosome.Y Chromosome is the sex chromosome found only in males.Male diploid cells have an X and Y chromosome.
*Gene linkage is the tendency of genes that are located proximal to each other on a chromosome to be inhereted together during meiosis.