Nucleotide Quiz
Questions: 16 · 10 minutes
1. A cell converts ATP into a small cyclic nucleotide that acts as an intracellular signaling molecule. Which molecule is produced?
Cyclic AMP
Cyclic GMP
ADP-ribose
Deoxyadenosine monophosphate
2. One DNA strand has the sequence 5′-AGTC-3′. Which sequence correctly represents the antiparallel complementary strand?
3′-AGTC-5′
3′-TCAG-5′
5′-TCAG-3′
3′-UCAG-5′
3. A laboratory must distinguish ATP from dATP. Which structural difference provides the clearest identification?
ATP contains a 2′ hydroxyl group, whereas dATP has hydrogen at the 2′ position
ATP has three phosphates, whereas dATP has two
ATP contains a 3′ hydroxyl group, whereas dATP does not
ATP contains adenine, whereas dATP contains guanine
4. Which three components make up a nucleotide?
A fatty acid, a pentose sugar, and a phosphate group
A nitrogenous base, a pentose sugar, and an amino group
A nitrogenous base, a pentose sugar, and one or more phosphate groups
A nitrogenous base, glycerol, and one or more phosphate groups
5. What type of covalent bond links adjacent nucleotides along a DNA or RNA strand?
Peptide bond
Phosphodiester bond
Glycosidic bond
Hydrogen bond
6. Which abbreviation represents a cytosine-containing ribonucleotide with one phosphate group?
CMP
dCMP
CDP
CTP
7. Which pair consists entirely of purine bases?
Guanine and uracil
Cytosine and thymine
Adenine and cytosine
Adenine and guanine
8. During nucleic acid synthesis, a polymerase normally attaches the incoming nucleotide to which part of the growing strand?
The nitrogenous base at the 5′ end
The 3′ hydroxyl group
The phosphate group at the 3′ end
The 2′ hydroxyl group
9. A double-stranded DNA molecule contains 28% adenine. Assuming standard base pairing, approximately what percentage is thymine?
22%
28%
44%
56%
10. When ATP loses its terminal phosphate group through hydrolysis, which products are most commonly formed?
AMP and pyrophosphate
Adenosine and three separate phosphate groups
ADP and inorganic phosphate
GTP and inorganic phosphate
11. A mutation replaces adenine with guanine at one position in DNA. How is this base substitution classified?
A transition, because one purine was replaced by another purine
A transversion, because one purine was replaced by another purine
A transversion, because a purine was replaced by a pyrimidine
A transition, because a purine was replaced by a pyrimidine
12. What distinguishes a nucleotide from a nucleoside?
A nucleotide lacks a sugar, while a nucleoside contains one
A nucleotide occurs only in DNA, while a nucleoside occurs only in RNA
A nucleotide contains a pyrimidine, while a nucleoside contains a purine
A nucleotide includes one or more phosphate groups, while a nucleoside does not
13. A researcher needs to distinguish an RNA nucleotide from the corresponding DNA nucleotide by examining only the sugar. What feature should the researcher look for?
A phosphate attached to the 5′ carbon
A nitrogenous base attached to the 1′ carbon
A hydroxyl group on the 2′ carbon
A hydroxyl group on the 3′ carbon
14. A DNA sample is broken down completely into individual nucleotides. Which sugar should those nucleotides contain?
Fructose
Ribose
Glucose
2-deoxyribose
15. In a typical nucleic acid backbone, a phosphodiester bond connects which two positions?
The 1′ carbon of one sugar and the base of the next nucleotide
The 2′ carbons of two neighboring sugars
The 3′ carbon of one sugar and the 5′ phosphate of the next nucleotide
The 5′ carbons of two neighboring sugars
16. Which nitrogenous base normally occurs in RNA in place of thymine?
Adenine
Cytosine
Guanine
Uracil