Nitrogenous base

Definition

Nitrogenous bases are organic molecules that contain nitrogen and act as the building blocks of nucleic acids, such as DNA and RNA. They play a crucial role in encoding genetic information.

5 Must Know Facts For Your Next Test

1. There are four types of nitrogenous bases in DNA: adenine (A), thymine (T), cytosine (C), and guanine (G).
2. In RNA, uracil (U) replaces thymine (T) as one of the nitrogenous bases.
3. Nitrogenous bases pair through hydrogen bonds: adenine pairs with thymine (or uracil in RNA) and cytosine pairs with guanine.
4. The sequence of nitrogenous bases along a DNA or RNA strand determines the genetic information carried by that molecule.
5. Nitrogenous bases can be classified into two categories: purines (adenine and guanine) and pyrimidines (cytosine, thymine, and uracil).

Review Questions

• What are the four nitrogenous bases found in DNA?
• How do nitrogenous bases pair in DNA and RNA?
• What is the difference between purines and pyrimidines?

Related terms

Nucleotide:

A compound consisting of a phosphate group, a sugar, and a nitrogenous base.

DNA Replication:

The process by which a DNA molecule makes an exact copy of itself.

RNA:

A nucleic acid involved in protein synthesis that contains ribose sugar and uses uracil instead of thymine.