What is the Difference Between XX and XY Chromosomes?

The X and Y chromosomes, also known as the sex chromosomes, determine the biological sex of an individual. The key differences between XX and XY chromosomes are as follows:

• Inheritance: Females inherit an X chromosome from the father for a XX genotype, while males inherit a Y chromosome from the father for a XY genotype. Mothers only pass on X chromosomes.
• Length: The Y chromosome is one-third as long as the X chromosome.
• Number of Protein-Coding Genes: The X chromosome has about 900 protein-coding genes, while the Y chromosome has significantly fewer.
• Sex-Determining Region: The Y chromosome contains the SRY gene, which is responsible for triggering the development of male reproductive organs. If the SRY gene doesn't produce a functional protein, the embryo will not develop testes despite having a Y chromosome.

In summary, the X and Y chromosomes differ in their length, protein-coding genes, and the presence of the SRY gene, which plays a crucial role in determining the biological sex of an individual.

Comparative Table: XX vs XY Chromosomes

The main difference between XX and XY chromosomes lies in the sex of the individual they determine. Here is a table highlighting the differences between XX and XY chromosomes:

In mammals, including humans, the sex chromosomes determine the sex of an individual. Females typically have two X chromosomes (XX), while males have one X and one Y chromosome (XY). X-linked genes are present on the X chromosome and are called sex-linked genes, as they have different inheritance patterns than genes on non-sex chromosomes (autosomes).

In females, one of the two X chromosomes undergoes X-inactivation, a process in which the inactivated X chromosome remains within a cell as a Barr body. This process does not occur in males, as they have one X and one Y chromosome.