$$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{ADP} + \mathrm{P} + \text{energy}$$

Question 1

Which of the following elements makes up the largest proportion of biological matter in the human body?

Accepted Answer

Oxygen (O)

Question 2

A neutral atom of potassium (K) has an atomic number of 19 and an atomic mass of 39. How many neutrons does it have?

Accepted Answer

$$20$$

Question 3

Which of the following best describes an isotope?

Accepted Answer

An atom with the same number of protons but a different number of neutrons

Question 4

If a sodium atom (Na) loses one electron, what is the resulting ion called and what is its charge?

Accepted Answer

Cation, positive charge

Question 5

Which of the following statements about water is FALSE?

Accepted Answer

Water molecules are held together by ionic bonds.

Question 6

A solution has a pH of 5. Compared to a solution with a pH of 7, how does its hydrogen ion concentration differ?

Accepted Answer

It is 100 times greater.

Question 7

Which of the following best describes a dehydration synthesis reaction?

Accepted Answer

A reaction that builds larger molecules by removing water

Question 8

Which of the following is a property of saturated fatty acids?

Accepted Answer

They are 'saturated' with hydrogen atoms and are solid at room temperature.

Question 9

Which class of organic molecules includes cholesterol, testosterone, and estrogen?

Accepted Answer

Steroids

Question 10

What is the main function of phospholipids in the human body?

Accepted Answer

Main component of cell membranes

Question 11

Which of the following best explains why carbon is so versatile in forming organic molecules?

Accepted Answer

It can form four covalent bonds due to its four valence electrons.

Question 12

A protein loses its shape and function when exposed to high heat or extreme pH. This process is called:

Accepted Answer

Denaturation

Question 13

Which of the following statements about enzymes is TRUE?

Accepted Answer

Enzymes lower the activation energy of a reaction.

Question 14

Which of the following best describes the structure of DNA?

Accepted Answer

Double-stranded with adenine, thymine, cytosine, and guanine as bases

Question 15

Which of the following is the correct equation for the hydrolysis of ATP?

Accepted Answer

$$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} ightarrow \mathrm{ADP} + \mathrm{P} + 	ext{energy}$$

Question 16

A solution is changed from pH 7 to pH 9. Which of the following statements is correct?

Accepted Answer

The solution has become more basic.

Question 17

Which of the following best describes a buffer in biological systems?

Accepted Answer

A substance that minimizes changes in pH by accepting or donating $$\mathrm{H}^+$$ ions

Question 18

Which of the following is a correct pairing of a macromolecule and its monomer?

Accepted Answer

Carbohydrate – Monosaccharide

Question 19

Which of the following best explains why water is considered a polar molecule?

Accepted Answer

Oxygen is more electronegative, creating partial charges on the molecule.

Question 20

Which of the following is a real-life example of a catabolic reaction in the human body?

Accepted Answer

Breakdown of starch into glucose during digestion

The Chemical Level of Organization: Elements and Atomic Structure in Anatomy & Physiology

Study Guide - Practice Questions