Cytosine makes up 42% of the nucleotides in a sample of DNA from an organism. Approximately what percentage of the nucleotides in this sample will be thymine?
1 Answer
Jul 2, 2016
8% will be thymine.
Explanation:
DNA is double stranded and nucleotides always appear in the same pairs:
- cytosine pairs with guanine (G-C)
- adenine pairs with thymine (A-T)
In this example cytosine makes up 42%, which means that guanine also makes up 42%. So 84% of the DNA is a G-C base pair.
This leaves 16% for the A-T base pair: 8% adenine and 8% thymine.