question_answer

Direction: Read the following and answer the questions from given below A codon is a trinucleotide sequence of DNA or RNA that corresponds to a specific amino acid. The genetic code describes the relationship between the sequence of DNA bases (A, C, G and T) in a gene and the corresponding protein sequence that it encodes. The cell reads the sequence of the gene in groups of three bases. There are 64 different codons out of which 61 specify amino acids while the remaining three are used as stop signals. So, each sequence of three codes for an amino acid and proteins are made up of sometimes hundreds of amino acids. So, the code that would make one protein could have hundreds, sometimes even thousands of triplets contained in it.

(v) Read the sequence of nucleotide in the given segment of mRNA and the respective amino acid sequence in the polypeptide chain to answer the question as follows.

\[\begin{align}   & mRNA \\  & polypeptide \\ \end{align}\] \[\frac{AUG\,\,UUU\,\,AUG\,\,CCU\,\,GUU\,\,UCU\,\,UAA}{Met-Phe-Met-Po-Val-Ser}\]

Following conclusion can be made from this

I. The nucleotide sequence of the DNA strand from which this mRNA was transcribed is TAC AAU TAC GCA CAA AGA ATT.

II. Codes for proline and valine are CCU and GUU, respectively.

III. AUG is also known as start codon.

IV. UAA does not code any amino acid.

A) I and II are incorrect

B) III and IV are correct

C) I and IV are incorrect

D) I, II and III and IV are correct