Principle Of Inheritance And Variation Question 163
Question: Assertion : In prokaryotes, there are three initiation factors used for protein synthesis. Reason : All the initiation factors have their own functions.
Options:
A) If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B) If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C) If the assertion is true but the reason is false
D) If both the assertion and reason are false
Show Answer
Answer:
Correct Answer: A
Solution:
In prokaryotes, three initiation factors are present - $ IF_1 $ , $ IF_2 $ , $ IF_3 $ .
All three factors are essential for initiation when natural mRNA are used as templates.
IF3 binds to the 30 S ribosomal subunit and is required for its binding to the mRNA starting site.
$ IF_3 $ also functions as a ribosome dissociation factors.
IF2 binds the initiator f Met- tRNA and carries it to the ribosome (together with GTP) in response to the first AUG codon.
$ IF_1 $ participates in the interaction between $ IF_2 $ and the initiator tRNA.
BETA
