Question

Which is the nitrogenous base present only in RNA, but not in DNA?

Answer 1

Hint: Both RNA and DNA consist of four nitrogenous bases. Both of them differ in just one base and have the other three bases same.

Complete step by step answer:
DNA and RNA are both made of nucleotides. DNA consists of four bases namely Adenine, Thymine, Guanine, and Cytosine. On the other hand, RNA also consists of four bases namely Adenine, Guanine, Uracil, and Cytosine. Uracil is the nitrogenous base present in RNA, but not in DNA. The molecular formula of Uracil is $$C_4{H}_4{N}_2{O}_2$$. Uracil is planar and unsaturated and has the ability to absorb light. It binds to adenine via 2 hydrogen bonds. Uracil has a single ring structure
Adenine and Guanine are referred to as purines, and two others, namely, Thymine/Uracil and Cytosine, are referred to as pyrimidines. In DNA, Thymine binds to Adenine while Guanine binds to Cytosine whereas in RNA, Uracil binds to Adenine while Guanine binds to Cytosine.
DNA is the constituent of the nucleus of the cell while the nucleolus of the cell is made up of RNA that is known for manufacturing proteins. The mRNA transports the formed proteins to the nucleus where DNA organises the genetic (hereditary) mechanism of the individual.

Hence, the correct answer is Uracil.

Note: A student can often confuse whether Uracil is present in RNA or DNA. Ensure to remember that Uracil is present in RNA and Thymine is present in DNA.