AP BIOLOGY

THE MOLECULAR BASIS OF INHERITANCE

DNA REPLICATION

Please wait while the activity loads.
If this activity does not load, try refreshing your browser. Also, this page requires javascript. Please visit using a browser with javascript enabled.

If loading fails, click here to try again

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]

Which nitrogen base does RNA have that DNA does not?

A	Thymine
B	Adenine
C	Uracil
D	Cytosine

Explanation:

Detailed explanation-1: -Uracil is the nitrogenous base present only in RNA, but not in DNA. Thymine is in DNA. DNA have thymine, guanine, adenine and cytosine. Thymine is replaced by uracil in RNA.

Detailed explanation-2: -Uracil (U) is one of the four nucleotide bases in RNA, with the other three being adenine (A), cytosine (C) and guanine (G). In RNA, uracil pairs with adenine. In a DNA molecule, the nucleotide thymine (T) is used in place of uracil.

Detailed explanation-3: -Nitrogen base not found in DNA is uracil. It is found only in RNA.

Detailed explanation-4: -RNA consists of four nitrogenous bases: adenine, cytosine, uracil, and guanine. Uracil is a pyrimidine that is structurally similar to the thymine, another pyrimidine that is found in DNA.

Detailed explanation-5: -Because thymine has a higher resistance to photochemical mutation and makes the genetic code more durable, DNA uses it instead of uracil.

There is 1 question to complete.