LIFE SCIENCE

Detailed explanation-1: -Each group of three bases in mRNA constitutes a codon, and each codon specifies a particular amino acid (hence, it is a triplet code). The mRNA sequence is thus used as a template to assemble-in order-the chain of amino acids that form a protein. Figure 2: The amino acids specified by each mRNA codon.

Detailed explanation-2: -(A) The small subunit and the mRNA bind to each other at the Shine-Dalgarno sequence. The start codon, AUG, is just downstream of this site. (B) The initiator tRNA becomes tagged with fMet and binds to the AUG codon on the mRNA.

Detailed explanation-3: -(KOH-don) A sequence of three consecutive nucleotides in a DNA or RNA molecule that codes for a specific amino acid. Certain codons signal the start or end of translation.

Detailed explanation-4: -The tRNA is located in the ribosome’s first docking site. This tRNA’s anticodon is complementary to the mRNA’s initiation codon, where translation starts. The tRNA carries the amino acid that corresponds to that codon. The next mRNA codon is now exposed in the ribosome’s other docking site.