Describe the structure of sex chromosomes.

Explanation

Structure of sex chromosomes :

1. Nuclei of human cells contain 22 autosomes and 2 sex chromosomes.
2. In females, the sex chromosomes are the 2X chromosomes. Males have one X-chromosome and one Y-chromosome.
3. X-chromosome is larger with more euchromatin and less heterochromatin while Y chromosome is smaller with more heterochromatin nnd less cuchromatin.
4. Y-chromosome is genetically less active due to lesser DNA present on it.
5. X and Y chromosomes have homologous and non-homologous regions.
6. X-linkcd genes are present on the homologous region of X chromosome while Y linked genes occur on the non-homologous region of Y chromosomes.