Question 1

Which of the following best describes an isotope?

Accepted Answer

Atoms of the same element whose nuclei contain different numbers of neutrons

Question 2

A patient is exposed to a radioactive isotope with a half-life of 6 hours. If the initial dose is 80 mg, how much isotope remains after 18 hours?

Accepted Answer

$80 \div 2^3 = 10$ mg

Question 3

Which type of chemical bond is responsible for the surface tension of water?

Accepted Answer

Hydrogen bond

Question 4

Which of the following best explains why water is an effective temperature buffer in the human body?

Accepted Answer

Water has a high heat capacity, absorbing and releasing heat slowly

Question 5

A solution has a pH of 6. Which of the following statements is correct?

Accepted Answer

The solution is acidic

Question 6

Which of the following is a function of buffers in the human body?

Accepted Answer

Buffers stabilize the pH of a solution by removing or replacing hydrogen ions

Question 7

Which of the following best describes a dehydration synthesis reaction?

Accepted Answer

A reaction in which water is removed to form a bond between molecules

Question 8

Which of the following is true about enzymes?

Accepted Answer

Enzymes lower the activation energy required for a reaction

Question 9

A protein loses its three-dimensional structure due to high fever. This process is called:

Accepted Answer

Denaturation

Question 10

Which of the following is a correct statement about the structure of DNA compared to RNA?

Accepted Answer

DNA contains thymine, while RNA contains uracil

Question 11

Which of the following best describes a molecule of glucose ($C_6H_{12}O_6$)?

Accepted Answer

A monosaccharide

Question 12

Which of the following is a property of lipids that distinguishes them from carbohydrates?

Accepted Answer

Lipids contain less oxygen than carbohydrates

Question 13

A solution contains $0.1$ mol of $NaCl$ dissolved in $1$ L of water. What is the concentration of $Na^+$ ions in the solution?

Accepted Answer

$0.1$ mol/L

Question 14

Which of the following is a correct description of a covalent bond?

Accepted Answer

A bond formed by the sharing of electron pairs between atoms

Question 15

Which of the following elements is essential for oxygen transport and energy capture in the human body?

Accepted Answer

Iron

Question 16

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

Accepted Answer

The folding that gives a polypeptide its three-dimensional shape

Question 17

Which of the following is a function of globular proteins in the human body?

Accepted Answer

Circulation in the blood and catalysis of chemical reactions

Question 18

Which of the following statements about electrolytes is correct?

Accepted Answer

Electrolytes are soluble inorganic substances that conduct electrical current in solution

Question 19

A patient has a blood pH of 7.0. What condition does this indicate?

Accepted Answer

Acidosis

Question 20

Which of the following best describes the role of functional groups in organic molecules?

Accepted Answer

They are responsible for the characteristic reactions of a particular compound

Chapter 2: The Chemical Level of Organization (BIO 141) – Study Notes

Study Guide - Practice Questions