Question

if an organism has 18 chromosomes in its somatic cells, how many chromosomes in its gametes? explain

Answer 1

Answer: 9 chromosomes

Somatic are all the cells present in an organism body except the gametic cells. They are diploid cells, i.e. chromosome in 2n form and they divide by mitotic division which is an equational division so even the new daughter cells form from them will have the same number of chromosome i.e. 2n and in this case 2n= 18.
while the gametes or gametic cells are reproductive cells that are used in reproduction. They are haploid cells i.e. they have n number fo chromosome. They are formed when gametocyte cells divide by meiotic division which a reductional division in which chromosome number is halved from the gametocytes. Since gametocytes are also diploid so the gametes form from by meiosis so they will have haploid or n number of chromosome in this it will be n= 9.