Question

Identify the incorrect statements regarding blood groups: 
Statements:
(1) The mother with Rh\(^{-}\) blood group develops passive immunity on administering IgM antibodies.
(2) Isoagglutinogens are sugar polymers bound to fatty acids on the RBC membrane.
(3) The alleles for Rh factor are located on three different loci on chromosome pair 9.
(4) The expression of ABO blood types in man is by three alleles of a single gene.

• A. II, IV
• B. I, II
• C. I, III
• D. II, III

Hint:

Understanding the genetics of blood groups can aid in comprehending various blood-related medical conditions and their treatment.

Answer 1

The Correct Option is C

To solve this problem, we need to identify the incorrect statements regarding blood groups based on the options provided.

1. Understanding the Statements:
Let's evaluate each statement:

• Statement I: "The mother with Rh- blood group develops passive immunity on administering IgM antibodies." - This statement is incorrect. Rh- mothers are at risk of Rh incompatibility with their Rh+ fetus, and passive immunity would not be conferred through IgM antibodies. Instead, IgG antibodies are involved in Rh incompatibility, not IgM. This makes the statement incorrect.
• Statement II: "Isoagglutinogens are sugar polymers bound to fatty acids on the RBC membrane." - This statement is correct. Isoagglutinogens are specific antigens (like A and B antigens) found on the surface of red blood cells (RBCs), which are made up of sugar polymers bound to lipid molecules.
• Statement III: "The alleles for Rh factor are located on three different loci on chromosome pair 9." - This statement is incorrect. The alleles for the Rh factor (like Rh+ and Rh-) are located at a single locus on chromosome 9, not three different loci. Therefore, this statement is incorrect.
• Statement IV: "The expression of ABO blood types in man is by three alleles of a single gene." - This statement is correct. The ABO blood group system is determined by three alleles (A, B, and O) of a single gene located on chromosome 9.

2. Conclusion:
Based on the analysis, the incorrect statements are Statements I and III.

Final Answer:
The correct answer is Option C: I, III.