Identify the wrong statement with reference to the gene ‘I’ that controls ABO blood groups.
Answer: (A) When IA and IB are present together, they express same type of sugar. Answer: (a) When IA and IB are present together, they express same type of sugar Solution: This is the WRONG statement.
- A.When IA and IB are present together, they express same type of sugar✓
- B.Allele ‘i’ does not produce my any sugar
- C.The gene (1) has three alleles
- D.A person will have only two of the three alleles
Correct Answer
(A) When IA and IB are present together, they express same type of sugar
Solution & Explanation
Answer: (a) When IA and IB are present together, they express same type of sugar Solution: This is the WRONG statement. IA and IB are codominant; in an AB individual each allele expresses its OWN distinct sugar (antigen A and antigen B), not the same sugar. The other statements are correct: allele i produces no sugar, gene I has three alleles (IA, IB, i), and any person carries only two of the three alleles. NCERT: Ch 15, p.195, line 22 — "two surface antigens ... on the RBCs namely A and B"