Question

The most abundant RNA of a cell is-
A. rRNA
B. tRNA
C. mRNA
D. None of the above

Answer 1

RNA was the first genetic material. There is enough evidence to suggest that essential life processes such as metabolism, translation, splicing, etc. evolved around the RNA. RNA stands for ribonucleic acid.

Complete answer:
There are three major types of RNA. An mRNA is also known as the Messenger RNA. tRNA which is also known as that transfer RNA. rRNA is also known as ribosomal RNA.
The mRNA provides a template for the translation (the process of protein synthesis from the genetic code that determines the sequence of amino acids in protein) to occur.
The tRNA brings the amino acid required for the formation of protein synthesis according to the genetic code.
The rRNA plays a structural and catalytic role during translation. rRNA is the only enzyme that acts as a catalyst and is not a protein in the organism. rRNA is also the most abundant RNA present.

So the correct answer is an option (A).

Additional information:
In DNA thymine is present as a nitrogenous base. Which is more stable than uracil which is present as a nitrogen base in RNA.

Note: As we know that RNA was the first genetic material then why DNA is used now.
RNA used to act as a genetic material as well as a catalyst.
But the RNA being the catalyst was more reactive and hence unstable.
Therefore DNA has evolved from RNA with the chemical modification that makes it more stable.
DNA being double standard and having complementary strands further resist change by evolving the process of repair.