Which base is in DNA but not RNA?

1 Answer
Feb 3, 2017

Thymine

Explanation:

Thymine (T) can not exist in the presence of oxygen. So it is replaced by U in RNA.

DNA stands for deoxi no oxygen. The DNA is found inside the nucleus membrane where it is protected from oxygen. RNA is a copy that can exist in the cell body where it dictates the production of proteins.

Oxygen has been present in the atmosphere from the beginning of the earth due to water being emitted by volcanos and broken down by ultraviolet light. The origin of Thymine containing DNA is a mystery.