Answer:
d. nitrogen-containing base
.
Explanation:
A nucleotide comprises a phosphate group, a pentose sugar and a nitrogenous base (nitrogen-containing base).
A nitrogenous base is a type of aromatic heterocyclic organic compound which essentially has nitrogen in it. The base can be a purine or pyrimidine. Purine nitrogenous bases are adenine (A) and guanine (G) while pyrimidine nitrogenous bases are cytosine (C), thiamine (T) and uracil (U).
Till the time a base is not attached to covalently linked phosphate group and a pentose sugar, it is known as nucleoside. But as soon as we attach any nitrogenous base to the nucleoside, a nucleotide is formed. So it means a nucleotide is nucleoside + nitrogenous base.
Examples are as under:
A nucleotide which has adenine as nitrogenous base is known as adenosine triphosphate (ATP) while a nucleotide which has guanine as nitrogenous base is known as Guanosine-5'-triphosphate (GTP).
The answer should be —10 — 5i
Answer:
Cell membranes serve as barriers and gatekeepers. ... Small polar molecules, such as water and ethanol, can also pass through membranes, but they do so more slowly. On the other hand, cell membranes restrict diffusion of highly charged molecules, such as ions, and large molecules, such as sugars and amino acids.
Explanation:
Hope it helps :)
Answer:
A
Explanation:
DNA must first be replicated before anything else occurs.
