Question

Find the correct statement.
(1) Generally a gene regulates a trait, but sometimes one gene has effect on multiple traits.
(2) The trait AB-blood group of man is regulated by one dominant allele and another recessive allele. Hence it is co-dominant.

• A. Both the Statements are wrong.
• B. Statement (1) is correct.
• C. Statement (2) is correct.
• D. Both Statements (1) and (2) are correct.

Answer 1

The Correct Option is B

Statement (1): This statement is correct. In genetics, while typically a single gene governs a single trait, pleiotropy occurs when one gene influences multiple traits. For example, a mutation in a single gene may result in various effects on different body systems or functions.

Statement (2): This statement is incorrect. The AB-blood group is an example of co-dominance, not involving one dominant allele and another recessive allele. The A and B alleles are both dominant. When both alleles are inherited, both traits are expressed equally, resulting in the AB blood group. There is no recessive allele in this case.

Thus, the correct answer is (B) : Statement (1) is correct.

Answer 2

The correct answer is: (B) Statement (1) is correct.

Let's analyze the two statements:

• Statement (1): "Generally a gene regulates a trait, but sometimes one gene has an effect on multiple traits."

  This statement is correct. A single gene typically regulates a specific trait, but some genes can affect multiple traits. This phenomenon is known as pleiotropy. For example, a gene may control several characteristics or phenotypic traits, such as coat color and eye color in certain animals.

• Statement (2): "The trait AB-blood group of man is regulated by one dominant allele and another recessive allele. Hence it is co-dominant."

  This statement is incorrect. The AB blood group is regulated by two co-dominant alleles, A and B. Both alleles are expressed equally, and neither is dominant or recessive. Therefore, the AB blood group is an example of co-dominance, but the explanation given is not accurate.

Thus, the correct answer is that Statement (1) is correct.