What are the four bases of DNA?

I have been searching through books and websites and I have been getting different answers. I do however think that it is Adenine and Guanine as the purines and Thymine and Cytosine as the pyrimidines.

2 Answers
Jun 17, 2018

You got it!


You are correct, the two purines are adenine and guanine, the two pyramidines are thymine and cytosine.

Now the source of confusion could be the inclusion of uracil, which is a nucleic acid of RNA . In DNA, thymine pairs with adenine, and uracil isn't used, because cyotisine can naturally turn into uracil. This changes the pattern of the DNA, as you would have a AU pair rather than a CG. So uracil is not used in DNA.

So, yeah, you're good.

Jun 17, 2018

The four bases of DNA are: adenine (A), thymine (T), guanine (G), and cytosine (C).


Only adenine can have a base pair with thymine and cytosine with guanine.

The types of nitrogenous bases include the purines and the pyrimidines.

Purines are chemicals that have double rings. Examples of this include adenine and guanine.

Pyrimidines are chemicals that have one ring: cytosine and thymine.



Hope this helps!