Question 1

Which of the following statements correctly describes the difference between Fischer and Haworth projections for glucose?

Accepted Answer

Fischer projections display the linear form of glucose, while Haworth projections depict the cyclic (ring) form.

Question 2

Which of the following is a distinguishing feature of amylopectin compared to amylose?

Accepted Answer

Amylopectin is highly branched due to $$\alpha(1 \rightarrow 6)$$ linkages, while amylose is mostly linear.

Question 3

Which of the following factors would most likely increase the melting temperature ($$T_m) of a $$DNA duplex?

Accepted Answer

Increasing the proportion of guanine-cytosine (G-C) base pairs.

Question 4

Which of the following best describes the role of lectins in biological systems?

Accepted Answer

They serve as recognition molecules by binding specific carbohydrate structures.

Question 5

A DNA sequence is palindromic if:

Accepted Answer

It reads the same from 5' to 3' on one strand and 3' to 5' on the complementary strand.

Question 6

Which of the following statements about glycosaminoglycans is correct?

Accepted Answer

They are long, unbranched polysaccharides containing repeating disaccharide units.

Question 7

Which of the following changes would most likely increase the fluidity of a biological membrane?

Accepted Answer

Increasing the proportion of unsaturated fatty acids.

Question 8

Which of the following is a key difference between RNA and DNA?

Accepted Answer

RNA contains uracil instead of thymine.

Question 9

Which of the following best describes the function of DNA polymerase in the polymerase chain reaction (PCR)?

Accepted Answer

It synthesizes new DNA strands by adding nucleotides to a primer.

Question 10

Which of the following structures is characteristic of a steroid molecule?

Accepted Answer

A four-ring fused hydrocarbon structure.

Question 11

Which of the following is true regarding the hydrogen bonding in DNA?

Accepted Answer

Guanine pairs with cytosine via three hydrogen bonds.

Question 12

Which of the following best describes the effect of increasing fatty acid chain length on membrane fluidity?

Accepted Answer

It decreases membrane fluidity.

Question 13

Which of the following is a function of glycoproteins in cell membranes?

Accepted Answer

They serve as recognition and signaling molecules.

Question 14

Which of the following best describes the structure of a glycerophospholipid?

Accepted Answer

A glycerol backbone with two fatty acids and a phosphate group.

Question 15

Which of the following is a common feature of palindromic DNA sequences?

Accepted Answer

They are recognized by many restriction enzymes.

Question 16

Which of the following is a correct description of the major groove in DNA?

Accepted Answer

It is the wider of the two grooves formed by the double helix and is often the site of protein binding.

Question 17

Which of the following is a function of tRNA in translation?

Accepted Answer

It carries amino acids to the ribosome and matches them to the mRNA codon.

Question 18

Which of the following best describes the effect of cholesterol on membrane fluidity at high temperatures?

Accepted Answer

Cholesterol decreases membrane fluidity at high temperatures.

Question 19

Which of the following is a correct statement about the attachment of sugars to proteins in glycoproteins?

Accepted Answer

Sugars can be attached to the amide nitrogen of asparagine (N-linked) or the hydroxyl oxygen of serine/threonine (O-linked).

Question 20

Which of the following is a correct description of the process of PCR (polymerase chain reaction)?

Accepted Answer

PCR amplifies DNA by repeated cycles of denaturation, primer annealing, and extension.

Biochemistry Study Guide: Carbohydrates, Nucleic Acids, and Lipids

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