AP BIOLOGY

Detailed explanation-1: -The mother gives an X chromosome to the child. The father may contribute an X or a Y. The chromosome from the father determines if the baby is born as male or female. The remaining chromosomes are called autosomal chromosomes.

Detailed explanation-2: -The X and Y chromosomes, also known as the sex chromosomes, determine the biological sex of an individual: 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).

Detailed explanation-3: -Genes on the X chromosome are said to be X-linked. X-linked genes have distinctive inheritance patterns because they are present in different numbers in females (XX) and males (XY). X-linked human genetic disorders are much more common in males than in females due to the X-linked inheritance pattern.

Detailed explanation-4: -If the egg receives another X chromosome from the sperm, the resulting individual is XX, forms ovaries, and is female; if the egg receives a Y chromosome from the sperm, the individual is XY, forms testes, and is male. The Y chromosome carries a gene that encodes a testis-determining factor.