Chapter 21, Problem 36A

Interpretation Introduction

Interpretation:

The difference between messenger RNA and transfer RNA needs to be explained along with their functions.

Concept Introduction:

Messenger RNA (known as mRNA) is formed from DNA in transcription process. Transfer RNA (known as tRNA) is the machinery for protein formation.

Answer to Problem 36A

mRNA is produced from DNA in transcription process. tRNA is small RNA fragments.

Sequence of amino acid is determined by mRNA sequence. tRNA performs the job of attaching particular amino acid as per requirement.

Explanation of Solution

Transfer RNA depends on messenger RNA for protein formation. The sequence of amino acid is determined by the mRNA sequence as the mRNA sequence dictates the tRNA which amino acid needed to be attached. tRNA performs the job to attach the amino acids as directed by mRNA sequences. mRNA is produced from DNA in transcription process. Here Splycing ( removal of introns) occurs and all the exons are connected to give the mRNA. Introns and exons are small nucleotides sequences.

Whereas tRNA is small RNA analogue which has complementary sequence with the mRNA and accordingly it attaches amino acids as specified by genetic code (three letter nucleotide sequence present in mRNA sequence).

For example if the mRNA sequence is 5’-AUGAUCUCGUAA-3’ then the amino acid sequence will be Met-Ile-Ser where AUG is start codon which codes for methionine. UAA is one of stop codons where protein synthesis stops.