Question

number correct 13
number incorrect 3
a nucleotide has three parts. what are they?
a. sugar, protein, and amino acid
b. nitrogen base, water, and amino acid
c. lipid, protein, and nucleic acid
d. sugar, phosphate, and nitrogen base

Explanation:

A nucleotide is the basic building block of nucleic acids (DNA and RNA). Its three components are a sugar (deoxyribose in DNA, ribose in RNA), a phosphate group, and a nitrogen - containing base (like adenine, guanine, cytosine, thymine in DNA or uracil in RNA).

• Option A: Amino acids are the building blocks of proteins, not nucleotides. So this option is incorrect.
• Option B: Water is not a component of a nucleotide, and amino acids are for proteins. So this option is incorrect.
• Option C: Lipids, proteins, and nucleic acids are macromolecules. A nucleotide is a part of nucleic acids, not a component of a nucleotide itself. So this option is incorrect.
• Option D: This option correctly lists the three parts of a nucleotide: sugar, phosphate, and nitrogen base.

Answer:

D. Sugar, phosphate, and nitrogen base