The AB blood group in the ABO system is an example of: MCQ with Answer and Explanation

The AB blood group in the ABO system is an example of:
A. Codominance
B. Multiple allelism only
C. Incomplete dominance
D. Pleiotropy
Answer: Option A
Solution (By JKSSB Mock Tests)
Codominance occurs when both alleles in a heterozygote are fully and equally expressed. In the ABO blood group system, the IA and IB alleles are codominant. An individual with the genotype IAIB will have both A and B antigens on the surface of their red blood cells, resulting in the AB blood type. It also involves multiple alleles (IA, IB, i).

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Biology Questions

Question #1
Consider statements about human nutrition: 1. A balanced diet provides all essential nutrients. 2. Malnutrition only refers to undernutrition. 3. Water is essential for life. Which are correct?
A. 2 and 3 only
B. 1 and 3 only
C. 1, 2 and 3
D. 1 and 2 only

Correct Answer: Option B


Explanation:
A balanced diet contains all the essential macronutrients (carbohydrates, proteins, fats) and micronutrients (vitamins, minerals) in the correct proportions required for optimal health, growth, and maintenance. Malnutrition is a broad term that refers to deficiencies, excesses, or imbalances in a person's intake of energy and/or nutrients; it includes both undernutrition (wasting, stunting) and overnutrition (overweight, obesity). Water is an essential nutrient, crucial for hydration, transport, and all biochemical reactions. Thus, statements 1 and 3 are correct.

This question belongs to: Science Biology
Question #2
The type of plant that has adapted to survive in very dry environments is called:
A. Halophyte
B. Xerophyte
C. Hydrophyte
D. Mesophyte

Correct Answer: Option B


Explanation:
Xerophytes (e.g., cactus, acacia) have adaptations like thick cuticle, sunken stomata, reduced leaves, and water-storing tissues to conserve water in arid habitats. Hydrophytes live in water, mesophytes in moderate conditions, halophytes in saline soils. Xerophytes minimize transpiration and maximize water uptake.

This question belongs to: Science Biology
Question #3
The hormone that stimulates the secretion of testosterone from Leydig cells is:
A. GnRH
B. LH
C. Inhibin
D. FSH

Correct Answer: Option B


Explanation:
Luteinizing hormone (LH) binds to Leydig cells in the testes, stimulating testosterone production. FSH stimulates Sertoli cells for spermatogenesis. GnRH is hypothalamic.

This question belongs to: Science Biology