In an inherited form of high cholesterol, rr individuals have a blood cholesterol level greater than 500 mg/dL, Rr individuals are near 300 mg/dL, while normal (RR ) cholesterol levels should be less than 200 mg/dL. The R allele is ___ to the r allele. a. Codominantb. Dominantc. Recessived. Homozygouse. Incompletely dominant

a. Codominant

Explanation:

The R allele is codominant to the r allele.

In codominance, the two alleles that make up a trait/gene exert equal effects on each other and therefore contribute equally to the phenotypic expression of the trait.

r in homozygous state conditions a blood cholesterol level that is greater than 500 mg/dl.

R in homozygous state conditions a blood cholesterol level that is less than 200 mg/dl.

Heterozygous condition, Rr conditions a blood cholesterol level near 300 mg/dl.

Hence, r and R exerted equal effects on each other which neither being dominant nor recessive. A clear-cut case of codominance.

The correct option is a.