The nitrogenous base found in RNA but not in DNA is

a. adenine.
b. cytosine.
c. guanine.
d. uracil.
e. thymine.


D

Biology & Microbiology

You might also like to view...

By _____, researchers had established how actin and myosin arrangements changed during muscle ____

a. 1924; relaxation b. 1954; contraction c. 1924; contraction d. 1994; relaxation e. 1904; stimulation

Biology & Microbiology

When carbon dioxide is absorbed into water, the solution becomes more

a. acidic. b. basic. c. warm. d. red.

Biology & Microbiology

In DNA replication, the leading strand of DNA ________, while the other newly forming strand, called the lagging strand, ________

A) is synthesized in the 5' ? 3' direction; the new DNA is synthesized in the 3' ? 5' direction B) is synthesized in the 3' ? 5' direction; the new DNA is synthesized in the 5' ? 3' direction C) does not require an RNA primer; an RNA primer is required D) is synthesized as a continuous chain; the new DNA is formed in a series of short, discontinuous fragments E) is synthesized in a series of short, discontinuous fragments; the new DNA is synthesized as a continuous chain

Biology & Microbiology

Why has finding an effective AIDS vaccine been so difficult?

A. Because it is caused by a virus. B. Because they have not yet isolated the virus that causes AIDS. C. Because the virus constantly mutates and so vaccines need to be made for all types. D. It is a sexually transmitted virus. E. The body does not make antibodies against the virus.

Biology & Microbiology