Purine-to-Purine Replacement
In DNA, replacement of one purine by another purine is known as:
- Transition — Correct Answer
- Transversion
- Translation
- Transformation
Explanation:
Correct Answer: Transition
Transition is the replacement of one purine by another purine (A↔G) or one pyrimidine by another pyrimidine (C↔T) in DNA.
Types of Nucleotide Substitution
| Type | Definition | Example |
|---|---|---|
| Transition | Purine → Purine OR Pyrimidine → Pyrimidine | A↔G; C↔T |
| Transversion | Purine → Pyrimidine OR Pyrimidine → Purine | A↔C; A↔T; G↔C; G↔T |
DNA Bases — Purines vs Pyrimidines
| Type | Bases | Memory Aid |
|---|---|---|
| Purines | Adenine (A), Guanine (G) | PuRine = Pure As Gold (A, G) |
| Pyrimidines | Cytosine (C), Thymine (T), Uracil (U) | CUT (C, U, T) |
Why Other Options Are Wrong
- Transversion: Purine ↔ Pyrimidine (opposite type replacement)
- Translation: Process of protein synthesis from mRNA — unrelated to mutation
- Transformation: Direct uptake of exogenous DNA by bacterial cell
📚 About this Topic — Animal Genetics & Breeding
This multiple choice question is from Animal Genetics & Breeding, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Genetics & Breeding to strengthen your preparation.
