Humans lack the enzyme to break $eta$-1,4-glycosidic bonds.

Question 1

Which of the following best describes an organic molecule?

Accepted Answer

A molecule primarily composed of carbon atoms bonded to hydrogen, oxygen, or nitrogen, and found in both living and non-living things.

Question 2

Carbon is considered a versatile building block in biological molecules because:

Accepted Answer

It can form up to four covalent bonds, allowing for diverse molecular structures.

Question 3

Which of the following is NOT a way in which carbon skeletons can vary?

Accepted Answer

Ability to form ionic bonds

Question 4

Which type of isomer has the same molecular formula but differs in the spatial arrangement of atoms around a double bond?

Accepted Answer

Cis-trans isomer

Question 5

Estradiol and testosterone are both steroid hormones. Which statement best explains their different effects in the body?

Accepted Answer

They have identical structures but different functional groups attached.

Question 6

Which functional group is commonly found in amino acids and is responsible for their acidic properties?

Accepted Answer

Carboxyl group ($-COOH$)

Question 7

During dehydration synthesis, which molecule is typically released as a byproduct?

Accepted Answer

Water ($H_2O$)

Question 8

Which bond forms between glucose and fructose to create sucrose?

Accepted Answer

Glycosidic bond

Question 9

Cellulose is difficult for humans to digest because:

Accepted Answer

Humans lack the enzyme to break $eta$-1,4-glycosidic bonds.

Question 10

Which of the following best describes the difference between saturated and unsaturated fatty acids?

Accepted Answer

Saturated fatty acids have no double bonds, while unsaturated fatty acids have one or more double bonds.

Question 11

Phospholipids are essential components of cell membranes because:

Accepted Answer

They have both hydrophilic and hydrophobic regions, allowing them to form bilayers.

Question 12

Which part of an amino acid determines its unique chemical properties?

Accepted Answer

The side chain (R group)

Question 13

Which of the following is NOT a major role of proteins in living things?

Accepted Answer

Storing genetic information

Question 14

How can you distinguish hydrophobic amino acid side chains from hydrophilic ones?

Accepted Answer

Hydrophobic side chains are nonpolar and lack charged or polar groups.

Question 15

Where are hydrophobic amino acids most likely to be found in a folded protein in an aqueous environment?

Accepted Answer

In the interior of the protein, away from water

Question 16

What is the primary structure of a protein?

Accepted Answer

The sequence of amino acids in a polypeptide chain

Question 17

Which two types of secondary structure are commonly found in proteins?

Accepted Answer

Alpha helix and beta sheet

Question 18

Which type of chemical bond is primarily responsible for maintaining the secondary structure of proteins?

Accepted Answer

Hydrogen bonds

Question 19

What does it mean to denature a protein, and what might cause denaturation?

Accepted Answer

Denaturation is the loss of a protein's three-dimensional structure due to changes in temperature, pH, or chemicals.

Question 20

According to the central dogma of molecular biology, what is the correct flow of genetic information?

Accepted Answer

$DNA \rightarrow RNA \rightarrow Protein$

Chapter 3: Biological Molecules and the Chemistry of Life – Study Guide

Study Guide - Practice Questions