Class 12 · Principles of Inheritance and Variation

Enzyme Defects in Genetic Disorders — NEET Biology

🔥 Predicted for NEET 2027
📖 NCERT Source

The normal/less efficient enzyme, or (ii) a non-functional enzyme, or (iii) no enzyme at all

NCERT Biology · Class 12 · Chapter 4 · Paragraph 38
Why This May Be Tested in NEET 2027

Adjacent to a frequently-asked paragraph in the same chapter.

Practice This Concept
QuestionPredicted for NEET 2027

Evaluate dominance: (1) Dominance depends on gene product and phenotype we examine. (2) Recessive phenotype results when non-functional enzyme produced. (3) Equivalent alleles can produce same genotype despite sequence changes. (4) In starch synthesis, heterozygotes show intermediate grain size if measured. (5) Therefore, dominance is autonomous property of a gene. Which statements are correct?

📖 Solution & NCERT Explanation
View solution & NCERT explanation

Correct answer: D 1, 2, 4

(1),(2),(4) correct; (3) false- sequence change will change the genotype; (5) false.

❓ Frequently Asked Questions
What does NCERT say about normalless efficient enzyme or?
The normal/less efficient enzyme, or (ii) a non-functional enzyme, or (iii) no enzyme at all
Has this concept appeared in NEET?
High probability for NEET 2027. Adjacent to a frequently-asked paragraph in the same chapter.
Which chapter is this from?
Principles of Inheritance and Variation, Class 12 NCERT Biology.

Through deep analysis of NEET and NTA, 176 of the 180 ReNEET 2026 (June 21) questions were already in the MedicNEET question bank before the exam.

176/180
of the ReNEET 2026 paper (all subjects) was already in the MedicNEET question bank

MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.

176 of 180 ReNEET 2026 questions traced to MedicNEET17,000+ Biology questionsHindi + English
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