Q. Consider the following statements regarding the nucleotide of DNA:
1. It is an organic molecule that is the building block of DNA and RNA.
2. It is made up of phosphate group and a nitrogenous base with no carbon sugar.
Which of the statements given above is/are correct?

[A] 1 only

[B] 2 only

[C] Both 1 and 2

[D] Neither 1 nor 2

Answer: A
Notes:

A nucleotide is an organic molecule that is the building block of DNA and RNA.  

  • They also have functions related to cell signaling, metabolism, and enzyme reactions.  
  • A nucleotide is made up of three parts: a phosphate group, a 5-carbon sugar, and a nitrogenous base.  
  • The four nitrogenous bases in DNA are adenine, cytosine, guanine, and thymine.  
  • RNA contains uracil, instead of thymine.  
  • A nucleotide within a chain makes up the genetic material of all known living things.  
  • They also serve a number of functions outside of genetic information storage, as messengers and energy moving molecules. 

Source: NCERT