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Question #45598
The Question
A genetic cross is performed between an individual with blood group AB and an individual with blood group O. Regarding the genetic basis, allelic interaction, and inheritance pattern of this cross, which of the following statements is INCORRECT?
Options
- A.
The alleles I^A and I^B produce slightly different forms of sugar polymers on the erythrocyte plasma membrane, while the i allele produces no sugar.
- B.
The offspring will exhibit a 1:1 phenotypic ratio of blood groups A and B, demonstrating that I^A and I^B are completely dominant over the i allele.
- C.
Because I^A and I^B lack a dominance hierarchy and express equally, their inheritance in this cross bypasses the Mendelian Law of Segregation.
- D.
Although the ABO blood grouping system is an example of multiple allelism in a population, any individual offspring from this cross will possess only two alleles.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
IA|IB|i_Alleles|ABO_Incompatibility
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students frequently conflate 'deviation from Mendelian dominance' (like co-dominance or incomplete dominance) with a 'violation of Mendelian segregation'.
The Law of Segregation has no exceptions; alleles always segregate during gametogenesis.
The trap relies on the student assuming that because AB blood type is a classic 'non-Mendelian' example, it bypasses all Mendelian laws.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Principles of Inheritance and Variation - Class 12 |
| Concept | Co-dominance Allelic Interaction |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |