Question 1

Which type of bond is primarily responsible for stabilizing the secondary structure (such as α-helix and β-pleated sheet) of a polypeptide chain?

Accepted Answer

Hydrogen bonds

Question 2

A protein loses its three-dimensional structure and biological activity when exposed to high temperatures. What is this process called?

Accepted Answer

Denaturation

Question 3

Which of the following best describes the primary structure of a protein?

Accepted Answer

The sequence of amino acids in the polypeptide chain

Question 4

Which of the following is a polysaccharide used for energy storage in animals?

Accepted Answer

Glycogen

Question 5

What is the chemical formula for most monosaccharides?

Accepted Answer

$C_nH_{2n}O_n$

Question 6

Which of the following is a major structural polysaccharide found in plant cell walls?

Accepted Answer

Cellulose

Question 7

Which type of lipid is the main component of biological membranes?

Accepted Answer

Phospholipids

Question 8

A phospholipid molecule contains which of the following components?

Accepted Answer

One glycerol, two fatty acids, and a phosphate group

Question 9

Which of the following statements about saturated and unsaturated fatty acids is correct?

Accepted Answer

Unsaturated fatty acids contain one or more double bonds and are usually liquid at room temperature

Question 10

Which of the following is NOT a function of carbohydrates in living organisms?

Accepted Answer

Catalyzing chemical reactions

Question 11

Which of the following correctly matches the type of bond with the protein structure it stabilizes?

Accepted Answer

Hydrogen bonds stabilize secondary structure

Question 12

Which of the following is a nucleotide component found in both DNA and RNA?

Accepted Answer

Adenine

Question 13

What type of reaction joins two monosaccharides to form a disaccharide?

Accepted Answer

Dehydration synthesis

Question 14

Which of the following best explains why phospholipids form bilayers in water?

Accepted Answer

Their hydrophilic heads interact with water while hydrophobic tails avoid water

Question 15

Which of the following is a correct pairing of a carbohydrate and its function?

Accepted Answer

Glycogen – energy storage in animals

Question 16

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

Accepted Answer

Adenine

Question 17

A mutation changes a single amino acid in the primary structure of a protein. Which level(s) of protein structure could be affected as a result?

Accepted Answer

Primary, secondary, tertiary, and quaternary structures

Question 18

Which of the following molecules is most likely to be found in the exoskeleton of an insect?

Accepted Answer

Chitin

Question 19

Which of the following best describes the difference between DNA and RNA?

Accepted Answer

DNA contains deoxyribose, while RNA contains ribose

Question 20

Which of the following is a steroid important for membrane structure in animal cells?

Accepted Answer

Cholesterol

Structure and Function of Large Biological Molecules

Study Guide - Practice Questions