NEET BIOLOGY

Detailed explanation-1: -Biologically male people always inherit their X chromosome from their mother. The X chromosome is about three times larger than the Y chromosome, containing about 900 genes, while the Y chromosome has about 55 genes. Female mammals have two X chromosomes in every cell. However, one of the X chromosomes is inactivated.

Detailed explanation-2: -While the chromosomes for other parts of the body are the same size and shape-forming an identical pairing-the X and Y chromosomes have different structures. The X chromosome is significantly longer than the Y chromosome and contains hundreds more genes.

Detailed explanation-3: -In the case of an X-linked disease, it is usually males that are affected because they have a single copy of the X chromosome that carries the disease-causing mutation. In females, the presence of a second, non-mutated copy may cause different, milder, or no symptoms of a sex-linked disorder.

Detailed explanation-4: -A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons (no male-to-male transmission). A condition is considered Y-linked if the altered gene that causes the disorder is located on the Y chromosome, one of the two sex chromosomes in each of a male’s cells.

Detailed explanation-5: -The Y chromosome is one-third the size of the X chromosome and contains about 55 genes while the X chromosome has about 900 genes. In genealogy, the male lineage is often traced using the Y chromosome because it is only passed down from the father.