Question 1

Which of the following best explains how variation in carbon skeletons contributes to molecular diversity in organic compounds?

Accepted Answer

Carbon skeletons can vary in length, branching, and ring structure, allowing for a wide variety of molecular shapes and functions.

Question 2

Which chemical group is most likely to act as an acid in biological systems, and why?

Accepted Answer

Carboxyl group, because it can release a hydrogen ion ($ \mathrm{H^+} $) into solution

Question 3

Which process is responsible for breaking down macromolecules into their monomers, and what is the main chemical reaction involved?

Accepted Answer

Hydrolysis; addition of water to break covalent bonds

Question 4

A patient is unable to digest lactose, a disaccharide. Which type of macromolecule is lactose, and what is its primary function in the body?

Accepted Answer

Carbohydrate; short-term energy source

Question 5

Which of the following best describes the structure of a phospholipid and its function in biological membranes?

Accepted Answer

A phospholipid has a hydrophilic head and two hydrophobic tails; it forms the bilayer of cell membranes.

Question 6

Which of the following is NOT one of the eight major functions of proteins?

Accepted Answer

Storing genetic information

Question 7

Which level of protein structure is primarily determined by hydrogen bonding between the backbone atoms, resulting in alpha helices and beta sheets?

Accepted Answer

Secondary structure

Question 8

A protein is exposed to high temperatures and extreme pH. Which of the following best describes what happens to the protein?

Accepted Answer

The protein denatures, losing its three-dimensional shape and function.

Question 9

Which of the following best describes the role of nucleic acids in living organisms?

Accepted Answer

They store and transmit genetic information.

Question 10

Which of the following scenarios best illustrates the importance of functional groups in biological molecules?

Accepted Answer

A fatty acid with a carboxyl group can act as an acid, while a hydrocarbon chain without it cannot.

Question 11

Which of the following best explains why cellulose and starch, both polymers of glucose, have different properties?

Accepted Answer

They have different types of glycosidic linkages between glucose monomers.

Question 12

A scientist is studying a protein that functions as an antibody. Which major function of proteins does this represent?

Accepted Answer

Defense

Question 13

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

Accepted Answer

The overall three-dimensional shape of a polypeptide, stabilized by interactions between side chains.

Question 14

Which environmental factor is most likely to disrupt the hydrogen bonds in a protein's secondary structure?

Accepted Answer

A change in pH

Question 15

Which of the following is a correct statement about dehydration synthesis?

Accepted Answer

It forms polymers from monomers by removing a molecule of water.

Question 16

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 possibly quaternary structures

Question 17

Which of the following best explains why saturated fats are solid at room temperature while unsaturated fats are liquid?

Accepted Answer

Saturated fats have no double bonds, allowing their molecules to pack closely together.

Question 18

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

Accepted Answer

The arrangement and interaction of multiple polypeptide subunits in a protein complex

Question 19

Which of the following is a real-world example of the importance of protein denaturation?

Accepted Answer

Cooking an egg causes the egg white proteins to denature and solidify.

Question 20

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

Accepted Answer

DNA contains the sugar deoxyribose and is double-stranded, while RNA contains ribose and is usually single-stranded.

Biological Macromolecules: Structure, Function, and Diversity

Study Guide - Practice Questions