Question

What is it called when a purine is replaced by a different purine?

1) Transition mutation
2) Transversion mutation
3) Silent mutation
4) Missense mutation

Answer 1

A purine replaced by a different purine is known as a transition mutation, which differs from a transversion mutation where a purine is replaced by a pyrimidine or vice versa.

Step-by-step explanation:

When a purine is replaced by a different purine in a DNA sequence, this type of mutation is referred to as a transition mutation. Transition mutations include cases where a base of the same kind is substituted for another, such as adenine (a purine) being replaced by guanine (also a purine).

In contrast, a transversion mutation occurs when a purine is replaced by a pyrimidine, or vice versa. Understanding these types of mutations is crucial for grasping the complexity of genetic variations and the potential impacts on protein synthesis.