Question

What is an anticodon?
(a) Paired triplet of bases on messenger RNA
(b) Unpaired triplet of bases on rRNA
(c) Paired triplet of bases on rRNA
(d) An unpaired triplet of bases in an exposed position of tRNA.

Answer 1

Hint: A codon is a sequence of three nitrogen bases that code for specific amino acids. It interacts with anticodon and brings particular amino acids by corresponding to the complementary codon in mRNA which codes information of DNA.

Complete answer:
Anticodon is a sequence of three unpaired nitrogen bases that are complementary to codon and occur over the tRNA. A tRNA forms a clover-like or L-shaped structure which has two recognition sites known as anticodon sites which are complementary to the codon of mRNA and amino acid binding site. A tRNA consists of two loops like pseudouridine and dihydrouridine. Pseudouridine attaches to the ribosome and dihydrouridine binds with amino acid activating enzymes. tRNA transfers amino acids from the cellular pool to ribosomes by polymerization to form polypeptides by transcribing the code of mRNA. tRNA is also known as an adapter molecule. For each amino acid, one tRNA is present.

Additional information:
A codon is a sequence of three nitrogen bases of DNA and RNA which specifies an amino acid. The nitrogen bases that present in a codon are adenine, guanine, cytosine, and uracil. A single codon code for only one amino acid allows metabolic machinery to operate different organisms. Amino acids having similar properties specified by related codons.

So, the correct answer is An unpaired triplet of bases in an exposed position of tRNA.

Note:
The translation process requires material like the ribosome, amino acid, tRNA, aminoacyl synthetase, mRNA, etc. In translation coded messages of mRNA from DNA get to change into polypeptide chains and form sequences of amino acids. A ribosome works as translation machinery with help of mRNA and tRNA.