Question 1

Which of the following best describes the difference between a ribonucleotide and a deoxyribonucleotide?

Accepted Answer

A deoxyribonucleotide has an —H instead of an —OH at C-2.

Question 2

Which of the following is NOT a component of a nucleoside?

Accepted Answer

A phosphate group

Question 3

Which of the following base compositions for double-stranded DNA is possible?

Accepted Answer

%A = 35, %G = 15, %C = 35, %T = 15, %U = 0

Question 4

Which of the following statements about the phosphodiester bonds in nucleic acids is correct?

Accepted Answer

They join the 3' hydroxyl of one nucleotide to the 5' hydroxyl of the next.

Question 5

In the Watson-Crick model of DNA structure (B-form DNA), which of the following is true?

Accepted Answer

The bases occupy the interior of the helix.

Question 6

Which of the following is the primary reason for the relative instability of RNA compared to DNA?

Accepted Answer

The presence of the 2'-hydroxyl group in RNA makes it susceptible to alkaline hydrolysis.

Question 7

Which of the following is a pyrimidine base found in nucleic acids?

Accepted Answer

Cytosine

Question 8

Which of the following is only found in RNA and not in DNA?

Accepted Answer

Uracil

Question 9

Which of the following is NOT a function of nucleotides and their derivatives?

Accepted Answer

Structural components of cell membranes

Question 10

Which of the following changes does NOT occur when double-stranded DNA is heated at neutral pH?

Accepted Answer

The covalent N-glycosidic bond between the base and the pentose breaks.

Question 11

B-form DNA in vivo is a _____-handed helix, A-form is _____-handed, and Z-form is _____-handed.

Accepted Answer

right; right; left

Question 12

Which of the following best describes the syn and anti conformations in nucleotides and nucleic acids?

Accepted Answer

Rotation around the sugar-base bond.

Question 13

Given the following structure, what is the full name of the nucleotide shown in the second image?

Accepted Answer

Adenosine triphosphate (ATP)

Question 14

Which of the following best explains why the sugar in DNA is called a 'deoxyribose'?

Accepted Answer

It lacks an oxygen atom at the 2' position compared to ribose.

Question 15

Which of the following best describes the linkage between the phosphate group and the sugar in a nucleotide?

Accepted Answer

Phosphoester bond

Question 16

Which of the following is the correct shorthand notation for a polynucleotide sequence composed of guanine, adenine, uracil, and cytosine?

Accepted Answer

GAUC

Question 17

Which of the following statements about the furanose form of sugars is correct?

Accepted Answer

It is a five-membered ring structure formed from an aldose sugar.

Question 18

Which of the following is a correct description of the bonds between phosphate groups in ATP?

Accepted Answer

Anhydride bonds

Question 19

Which of the following is a purine base?

Accepted Answer

Adenine

Question 20

Which of the following best describes the role of nucleotides as enzyme cofactors?

Accepted Answer

They participate in redox reactions and group transfer reactions.

Study Guide: Nucleotides and Nucleic Acids (BCH20002 – Introduction to Biochemistry)

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