Question

Which one of the following describes best about co-dominance of alleles?

• A. one is recessive
• B. both are dominant
• C. one is dominant
• D. both are recessive

Hint:

In co-dominance, both alleles in a heterozygote are expressed, and both show their phenotypic effects.

Answer 1

The Correct Option is B

Step 1: Understanding co-dominance.
Co-dominance occurs when both alleles contribute equally and visibly to the organism's phenotype. In this case, both alleles are dominant and neither allele is recessive.
Step 2: Analyzing the options.
(A) one is recessive: Incorrect — Co-dominance involves both alleles being dominant.
(B) both are dominant: Correct — In co-dominance, both alleles express their traits simultaneously.
(C) one is dominant: Incorrect — Both alleles are dominant in co-dominance.
(D) both are recessive: Incorrect — Recessive alleles do not show their effect when co-dominance occurs.
Step 3: Conclusion.
The correct answer is (B) both are dominant, as co-dominance involves both alleles contributing equally to the phenotype.