Question

The law of dominance is not universally applicable because in some organisms few characters are ..............

• A. completely dominant.
• B. both dominant and recessive.
• C. completely recessive.
• D. incompletely dominant.

Hint:

Incomplete dominance occurs when neither allele is completely dominant over the other, resulting in a blending of traits.

Answer 1

The Correct Option is D

Step 1: Understanding the law of dominance.
Mendel’s law of dominance states that when two alleles are present, one allele may mask the expression of the other. However, in some organisms, incomplete dominance occurs, where neither allele completely dominates the other.
Step 2: Analyzing the options.
(A) completely dominant: Incorrect. Completely dominant alleles follow the law of dominance.
(B) both dominant and recessive: Incorrect. The law of dominance does not typically apply in such cases.
(C) completely recessive: Incorrect. Recessive alleles are masked by dominant alleles, and this is consistent with Mendel’s laws.
(D) incompletely dominant: Correct. In incomplete dominance, neither allele completely dominates, leading to intermediate phenotypes.
Step 3: Conclusion.
The correct answer is (D) incompletely dominant, as this is the condition where the law of dominance does not fully apply.