Class 12th Biology 2012 Set2 Delhi Board Paper Solution
It is established that RNA is the first genetic material. Explain giving three reasons.
OR
(a) Name the enzyme responsible for the transcription of tRNA and the amino acid the initiator tRNA gets linked with.
(b) Explain the role of initiator tRNA in initiation of protein synthesis.
RNA was the first genetic material in cells because • RNA is capable of both storing genetic information and catalyzing chemical reactions • Essential life processes (such as metabolism, translation, splicing, etc.), evolved around RNA. • It has the tendency of self replication. OR (a) RNA polymerase III is responsible for transcription of tRNA and methionine is the amino acid that gets linked with the initiator tRNA. (b) Initiator tRNA carries amino acid methionine at its amino acid binding site and has anticodon UCA at its anticodon binding site. Initiator tRNA binds with the codon (AUG) present on the mRNA and in this way the initiator tRNA plays a role in initiation of protein synthesis.
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