question_answer

Direction (11 - 15): Nucleic acids are the polymers of nucleotides which in turn consist of a base, a pentose sugar and phosphate moiety. Nucleic acids are responsible for the transfer of characters from parents of offsprings. There are two types of nucleic acids - DNA and RNA. DNA contains a five carbon sugar molecule called 2-deoxyribose whereas RNA contains ribose. Both DNA and RNA contain adenine, guanine and cytosine. The fourth base is thymine in DNA and uracil in RNA. The structure of DNA is a double strand whereas RNA is a single strand molecule. DNA is the chemical basis of heredity and have the coded message for proteins to be synthesised in the cell. There are three types of RNA - mRNA, rRNA and tRNA which actually carry out the protein synthesis in the cell.

(Source : N.C.E.R.T. book, Class XII)

The RNA which carries the genetic information from DNA for protein synthesis is

A) r-RNA                           

B) t-RNA

C) m-RNA             

D) All the three