Question

Recessive sex linked disorders are more common in males than in females because

• A. Males have no corresponding allele on their X chromosome to mask the allele carried on their Y chromosome
• B. Males have no corresponding allele on their Y chromosome to mask the allele carried on their X chromosome
• C. Males carry all sex-linked traits on their Y chromosome
• D. Females always carry at least one dominant allele for sex-linked traits because they have two X chromosomes
• E. Females compensate by "turning" off the recessive allele through dosage compensation

Answer 1

The correct option is B Males have no corresponding allele on their Y chromosome to mask the allele carried on their X chromosome

Sex-linked disorders are any disease or abnormality that is determined by the sex hormones They are generally recessive in nature.

X-linked recessive diseases usually occur in males. Males have only one X chromosome. A single recessive gene on that X chromosome will cause the disease. The Y chromosome is the other half of the XY gene pair in the male. However, the Y chromosome doesn't contain most of the genes on the X chromosome. Because of that, it doesn't protect the male. Diseases such as haemophilia and Duchenne muscular dystrophy occur from a recessive gene on the X chromosome. Thus, the correct answer is option B.