Answer:
In organisms during cell division, DNA is present in packaged structure called "chromosomes" with a constriction point called the centromere giving X-shape to the chromosomes. This forms a complete set of chromosome.The number of chromosomes present in the nucleus of the cell is known as ploidy number represented by "n".
Based on the number of chromosomes, cell is usually divided into: Haploid cell and diploid cell.
Haploid cells (n): are the cells with only one complete set or chromosomes like gamete cells while
Diploid cells (2n): are the cells with 2 sets or pair of chromosomes like somatic cells.