The phenotype for red-green colorblindness is more common amongst human males than females. This suggests what form of inheritance?

A. autosomal inheritance
B. codominance
C. sex-linked
D. incomplete dominance

Red-green colorblindness is more common in males due to being an X-linked recessive trait. Males have only one X chromosome, so they express the trait if they inherit the allele. Therefore, the correct answer is C. sex-linked.
;

Answered by Anonymous | 2025-07-18

The question asks about the pattern of inheritance for red-green colorblindness, which is more commonly found in males than females. This form of inheritance is known as sex-linked inheritance , which corresponds to option (C).
Sex-linked inheritance typically involves genes located on the sex chromosomes, particularly the X chromosome. Humans have two types of sex chromosomes: X and Y. Females have two X chromosomes (XX), while males have one X chromosome and one Y chromosome (XY).
Red-green colorblindness is caused by a recessive allele on the X chromosome. Here's why it is more common in males:

Males have a single X chromosome : If a male inherits the X chromosome carrying the allele for red-green colorblindness, he will express the trait because he does not have a second X chromosome to possibly carry a normal allele.

Females have two X chromosomes : A female must inherit two copies of the colorblind allele, one from each parent, to express red-green colorblindness. This is less common because if she inherits one normal allele on one X chromosome, it usually masks the effect of the recessive allele on the other X chromosome.


This explains the higher prevalence of red-green colorblindness in males compared to females, indicating that the inheritance type is sex-linked.

Answered by OliviaLunaGracy | 2025-07-21