Name the nitrogen base present only in DNA not in RNA.

Hint: There are four bases present in DNA. The four bases that are present in DNA are adenine, thymine, guanine and cytosine. DNA stands for deoxyribonucleic acid while RNA stands for ribonucleic acid.

Complete step by step answer:
-There are four bases present in DNA. The four bases that are present in DNA are adenine, thymine, guanine and cytosine. DNA stands for deoxyribonucleic acid while RNA stands for ribonucleic acid.
-Thymine is the base that is present in DNA but is absent in RNA.
-Let us look at what DNA and RNA are and what are their properties. There are two main types of nucleic acids DNA and RNA.
DNA stands for Deoxyribonucleic acid and RNA stand for ribonucleic acid. DNA is found in all living organisms and is a genetic material.
RNA on the other hand is involved in protein synthesis. There are three types of RNA that are involved in protein synthesis are rRNA , tRNA and micro RNA There is another type of RNA that is messenger RNA which acts as an intermediate aur messenger between DNA and different cells.
DNA and RNA have the monomer known as nucleotide. Three components are there in nucleotides
1. Nitrogenous base
This contains carbon and nitrogen that is why it is called an organic molecule. It contains an amino group and the group has a tendency to attract extra hydrogen and hence it will act as a base.
2. Pentose sugar
The sugar present in DNA is deoxyribose and in RNA there is ribose sugar. The position of hydroxyl group on the second carbon Alpha drivers and hydrogen on second carbon of deoxyribose makes the two sugars different.
3. A phosphate group
A group attached with 5 carbon of one sugar and the hydroxyl group of 3 carbon of the sugar of the next nucleotide is phosphate group.

Note:
A molecule of DNA is attached with Chromosomes (thread like structures), along with a unit of protein, they carry unique characteristics. If you unbound the entire DNA in your body, and place them end to end they will travel from earth to sun and back 600 times.