GlossariesGCSE GlossariesGCSE Biology GlossaryDna Bases

Dna Bases - GCSE Biology Definition

Reviewed by: Lára Marie McIvor

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DNA bases are the building blocks of DNA, which is the genetic material found in all living things. There are four different types of bases in DNA: adenine (A), thymine (T), cytosine (C), and guanine (G). These bases pair up in a specific way: adenine pairs with thymine, and cytosine pairs with guanine. This pairing forms the "rungs" of the DNA's "ladder" shape, known as a double helix. The order of these bases in DNA determines the genetic instructions for building and maintaining an organism, much like how letters form words that create instructions in a recipe.

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Lára Marie McIvor

Reviewer: Lára Marie McIvor

Expertise: Biology, Psychology & Sociology Subject Lead

Lára graduated from Oxford University in Biological Sciences and has now been a science tutor working in the UK for several years. Lára has a particular interest in the area of infectious disease and epidemiology, and enjoys creating original educational materials that develop confidence and facilitate learning.

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