Principles of Inheritance and Variation NEET PYQs (1988–2026)

Solved Principles of Inheritance and Variation PYQs

3 recent questions with answers. The full set of 233 is free to practise.

1. NEET 2026HardIncomplete dominance, codominance, multiple alleles
   Q1

   Match List I with List II:
   
   List-I:
   
   A. Incomplete dominance,
   
   B. Co-dominance,
   
   C. Pleiotropy,
   
   D. Polygenic inheritance
   
   List-II:
   
   I. Human skin colour,
   
   II. Inheritance of flower colour in
   
   Antirrhinum sp.,
   
   III. Phenylketonuria disease in humans,
   
   IV. ABO blood groups
   
   Choose the correct answer from the options given below:

   • AA-II, B-IV, C-III, D-I
   • BA-I, B-III, C-II, D-IV
   • CA-I, B-IV, C-III, D-II
   • DA-II, B-I, C-III, D-IV

   Show answer & solution

   Correct answer: (A)

   Incomplete dominance -- Antirrhinum (II); Co-dominance -- ABO blood groups (IV); Pleiotropy -- Phenylketonuria (III); Polygenic – skin colour (I). So A-II, B-IV, C-III, D-I.
2. NEET 2026HardSex determination and sex-linked inheritance
   Q2

   Which of the following statements are true with reference to the sex-determination in honeybees?
   
   A. An offspring formed from the union of a sperm and an egg, develops as a female (queen or worker).
   
   B. An unfertilized egg develops as a male by parthenogenesis.
   
   C. A male has half the number of chromosomes than that of a female.
   
   D. Males produce sperms by meiosis.
   
   E. Honeybees have a haplodiploid sex-determination system.
   
   Choose the correct answer from the options given below:

   • AA, B, C and E only
   • BB, C, D and E only
   • CA, B, C and D only
   • DA, B, D and E only

   Show answer & solution

   Correct answer: (A)

   A, B, C, E are correct. D is false (males produce sperms by mitosis, not meiosis). So A, B, C, E.
3. NEET 2026MediumMutations and genetic disorders
   Q3

   Which one of the following disorders is caused by the substitution of Glutamic acid (Glu) by Valine (Val) at the sixth position of the beta globin chain of the haemoglobin molecule?

   • AThalassemia
   • BSickle-cell anaemia
   • CPhenylketonuria
   • DHaemophilia

   Show answer & solution

   Correct answer: (B)

   Sickle-cell anaemia is caused by Glu→Val substitution at position 6 of beta globin.

Topic-wise question count

Where NEET has asked from Principles of Inheritance and Variation, most frequent first.

• Mutations and genetic disorders64
• Sex determination and sex-linked inheritance46
• Mendel's laws of inheritance38
• Monohybrid and dihybrid crosses32
• Incomplete dominance, codominance, and multiple alleles27
• Linkage, crossing over, and recombination19
• Chromosomal theory of inheritance6
• Incomplete dominance, codominance, multiple alleles1

Year-wise Principles of Inheritance and Variation questions in NEET

Number of questions from this chapter in each year's paper(s).