Question 1

Which of the following best describes a compound?

Accepted Answer

A substance consisting of two or more different elements combined in a fixed ratio

Question 2

Which four elements make up approximately 96% of the mass of living matter?

Accepted Answer

Carbon, Hydrogen, Oxygen, Nitrogen

Question 3

What is the main difference between an essential element and a trace element in biology?

Accepted Answer

Essential elements are required in large amounts, while trace elements are required in minute quantities

Question 4

Which subatomic particle is directly involved in chemical reactions between atoms?

Accepted Answer

Electron

Question 5

If an atom has an atomic number of 6 and an atomic mass of 14, how many neutrons does it have?

Accepted Answer

$14 - 6 = 8$

Question 6

Which of the following best describes an isotope?

Accepted Answer

Atoms of the same element with different numbers of neutrons

Question 7

Which type of chemical bond is the strongest under physiological conditions?

Accepted Answer

Covalent bond

Question 8

What is the purpose of the periodic table in biology?

Accepted Answer

To organize elements by their properties and predict their chemical behavior

Question 9

Elements in the same column (group) of the periodic table have which of the following in common?

Accepted Answer

The same number of valence electrons

Question 10

Why do electrons in higher energy levels have more potential energy?

Accepted Answer

They are farther from the nucleus and thus have more stored energy due to their position

Question 11

Which of the following best explains why the shape of a molecule is important in biology?

Accepted Answer

Molecular shape determines how molecules interact with each other, such as enzyme-substrate specificity

Question 12

Which of the following is an example of a real-world application of radioactive isotopes in medicine?

Accepted Answer

Using $^{18}F$ in PET scans to detect cancerous tissues

Question 13

Which of the following best describes chemical equilibrium?

Accepted Answer

The rate of the forward reaction equals the rate of the reverse reaction

Question 14

Which of the following best describes electronegativity?

Accepted Answer

The ability of an atom to attract electrons in a covalent bond

Question 15

Which of the following is a correct statement about ions?

Accepted Answer

An anion is an ion with a negative charge

Question 16

Which of the following best explains why morphine and endorphins can have similar effects in the human body?

Accepted Answer

They have similar molecular shapes, allowing them to bind to the same receptors

Question 17

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

Accepted Answer

A covalent bond in which electrons are shared unequally between atoms

Question 18

Which of the following is the correct formula for calculating the atomic mass of an atom?

Accepted Answer

$	ext{Atomic mass} = 	ext{Number of protons} + 	ext{Number of neutrons}$

Question 19

Which of the following best describes the two parts of a chemical reaction?

Accepted Answer

Reactants and products

Question 20

Which of the following statements about the periodic table is correct?

Accepted Answer

Elements in the same row have the same number of electron shells

Atoms, Elements, and Chemical Bonds: Foundations of General Biology

Study Guide - Practice Questions