AP BIOLOGY

Detailed explanation-1: -Recessive X-linked traits appear more often in males than females because, if a male receives a “bad” allele from his mother, he has no chance of getting a “good” allele from his father (who provides a Y) to hide the bad one.

Detailed explanation-2: -X-linked recessive diseases most often occur in males. Males have only one X chromosome. A single recessive gene on that X chromosome will cause the disease.

Detailed explanation-3: -Fathers cannot pass X-linked recessive conditions to their sons. When a son inherits a mutated gene on the X chromosome from his mother, the genetic condition is more likely to occur. X-linked recessive conditions most often occur in males.

Detailed explanation-4: -Females have two X chromosomes in their cells, while males have one X and one Y. 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.

Detailed explanation-5: -X-linked dominant disorders are seen more commonly in females than in males, or in the case of some diseases, affect only females. In the latter case, it is thought that the hemizygous males are so severely affected, they do not survive.