Question

Match List-I with List-II


List-I & List-II
(A). Incomplete dominance & (I). Albinism in plants
(B). Co dominance & (II). Heterozygous phenotype is intermediate to homozygous parents
(C). Multiple alleles & (III). Heterozygote phenotype is mixture of phenotypes of homozygous parents
(D). Lethal alleles & (IV). Coat colour in rabbits


Choose the correct answer from the options given below:

• (A) - (III), (B) - (II), (C) - (IV), (D) - (I)
• (A) - (II), (B) - (III), (C) - (I), (D) - (IV)
• (A) - (II), (B) - (III), (C) - (IV), (D) - (I)
• (A) - (III), (B) - (II), (C) - (I), (D) - (IV)

Hint:

In incomplete dominance, the heterozygote is an intermediate blend, whereas in codominance, both parental traits are expressed distinctly and simultaneously.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Extensions of Mendelian genetics include various allelic interactions that modify standard inheritance patterns and ratios.

Step 2: Detailed Explanation:
Let us match each genetic phenomenon with its correct definition or example:
- (A) Incomplete dominance: The phenotype of the heterozygote is intermediate between those of the two homozygotes (e.g., pink flowers in Mirabilis jalapa), so (A) matches with (II).
- (B) Codominance: The heterozygote simultaneously expresses both parental phenotypes (e.g., AB blood group or mixed hair color in cattle), so (B) matches with (III).
- (C) Multiple alleles: A single gene locus has three or more alternative alleles in a population (e.g., coat color in rabbits, which is controlled by a series of four alleles), so (C) matches with (IV).
- (D) Lethal alleles: Allelic combinations that cause the premature death of the organism (e.g., homozygous recessive albinism in plants, which prevents photosynthesis), so (D) matches with (I).
This gives the correct sequence: (A)-(II), (B)-(III), (C)-(IV), (D)-(I).

Step 3: Final Answer:
Hence, the correct option is (C).