Class 12th Biology 2017 Set1 Outside Delhi Board Paper Solution
Describe the structure and function of a t-RNA molecule. Why is it referred to as an adapter molecule ?
The secondary structure of t-RNA has been depicted that looks like a clover leaf. The t-RNA is a compact molecule which looks like inverted L.
Function: t-RNA has anticodon loop that has bases complimentary to the code, and it is also has an amino acid acceptor end to which it binds to amino acids. t-RNA are specific for each amino acid.
It refers as an adaptor molecule because on one hand read the code and on another hand would bind to spefic amino acids.
t-RNA has five arms or loops
(i) Anticodon loop : - Which has bases complementary to the code.
(ii) Amino acid acceptor end : - To which amino acid binds.
(iii) T-loop : - Which help in binding to ribosome.
(iv) D-loop : - Which help in binding amino acyl synthetase.
(v) Variable loop : - No function known.
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