Question 1

Which of the following best describes the difference between an ionic bond and a covalent bond?

Accepted Answer

An ionic bond involves the transfer of electrons from one atom to another, while a covalent bond involves the sharing of electrons between atoms.

Question 2

Which of the following elements is NOT one of the six most common elements found in living organisms (CHONPS)?

Accepted Answer

Magnesium

Question 3

A solution has a hydrogen ion concentration of $$[H^+] = 1 	imes 10$$^{-5}$$ M. What is its pH?

Accepted Answer

$$pH = 5$$

Question 4

Which functional group is represented by the structure $$-OH$$ and is commonly found in alcohols?

Accepted Answer

Hydroxyl group

Question 5

What type of reaction is responsible for joining two monosaccharides to form a disaccharide?

Accepted Answer

Dehydration synthesis

Question 6

Which of the following best explains why water is an excellent solvent for ionic compounds like NaCl?

Accepted Answer

Water forms hydrogen bonds with the ions, surrounding and separating them.

Question 7

Which level of protein structure is defined by the sequence of amino acids in a polypeptide chain?

Accepted Answer

Primary structure

Question 8

A protein loses its three-dimensional structure and function when exposed to high heat. This process is called:

Accepted Answer

Denaturation

Question 9

Which of the following macromolecules is NOT correctly matched with its monomer?

Accepted Answer

Carbohydrate – Fatty acid

Question 10

Which of the following statements about DNA and RNA is correct?

Accepted Answer

DNA is double-stranded and contains deoxyribose; RNA is single-stranded and contains ribose.

Question 11

Which of the following best describes the role of phospholipids in biological membranes?

Accepted Answer

They form a bilayer with hydrophobic tails facing inward and hydrophilic heads facing outward.

Question 12

Which of the following is a polysaccharide found in plant cell walls and is not digestible by humans?

Accepted Answer

Cellulose

Question 13

A solution with a pH of 3 has how many times more hydrogen ions than a solution with a pH of 6?

Accepted Answer

1000 times more

Question 14

Which of the following is true regarding the formation of a peptide bond?

Accepted Answer

It is formed by dehydration synthesis between the amino group of one amino acid and the carboxyl group of another.

Question 15

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

Accepted Answer

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

Question 16

Which of the following statements about acids and bases is correct?

Accepted Answer

Acids increase the concentration of $$H^+$$ ions in solution.

Question 17

Which of the following is a correct representation of the formula for calculating pH?

Accepted Answer

$$pH = -\log[H^+]$$

Question 18

Which of the following is a function of proteins in living organisms?

Accepted Answer

Catalyzing biochemical reactions

Question 19

Which of the following statements about macromolecule synthesis is correct?

Accepted Answer

Dehydration synthesis reactions join monomers to form polymers.

Question 20

Which of the following best explains why cholesterol is important in eukaryotic cell membranes?

Accepted Answer

It provides rigidity and fluidity to the membrane.

Chapter 2: Chemical Principles and Macromolecules in Microbiology

Study Guide - Practice Questions