Question 1

Which of the following best describes the relationship between atoms, elements, and matter as depicted in the concentric circle diagram?

Accepted Answer

Atoms are the smallest units of elements, and all elements are forms of matter.

Question 2

A sodium atom loses one electron to become a sodium ion. What is the resulting charge and why?

Accepted Answer

The sodium ion has a positive charge because it lost an electron.

Question 3

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes of an element have the same number of protons but different numbers of neutrons.

Question 4

Which of the following best explains why water is considered a compound and not just a molecule?

Accepted Answer

Water is made of two or more different elements chemically bonded together.

Question 5

Which of the following is a correct application of the octet rule?

Accepted Answer

Atoms are most stable when their outermost shell contains 8 electrons.

Question 6

A patient is injected with a radioactive isotope to monitor blood circulation. Which isotope is most likely used for this purpose?

Accepted Answer

Sodium-24

Question 7

Which of the following best describes the difference between ionic and covalent bonds?

Accepted Answer

Ionic bonds involve the transfer of electrons, while covalent bonds involve the sharing of electrons.

Question 8

Which of the following is a real-life example of a redox (oxidation-reduction) reaction in the human body?

Accepted Answer

The conversion of glucose and oxygen to carbon dioxide and water during cellular respiration.

Question 9

Which of the following best explains why antioxidants are important for human health?

Accepted Answer

They neutralize free radicals by donating electrons, preventing cellular damage.

Question 10

A solution has a pH of 4. Which of the following statements is true about this solution?

Accepted Answer

It is acidic and has a higher concentration of H$$^+$$ ions than OH$$^-$$ ions.

Question 11

Which of the following best describes the role of enzymes in chemical reactions?

Accepted Answer

Enzymes speed up chemical reactions by lowering the activation energy.

Question 12

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

Accepted Answer

Serves as a solvent, temperature regulator, and shock absorber.

Question 13

Which of the following best explains why sodium chloride (NaCl) is classified as an electrolyte?

Accepted Answer

It forms ions when dissolved in water, allowing electrical conduction.

Question 14

Which of the following is a correct example of a synthesis reaction?

Accepted Answer

A + B $$\rightarrow AB$$

Question 15

A patient with diabetic ketoacidosis experiences protein denaturation. What does this mean at the molecular level?

Accepted Answer

The protein unfolds and loses its functional shape.

Question 16

Which of the following best describes the difference between a monomer and a polymer?

Accepted Answer

A monomer is a single building block, while a polymer is made of many monomers joined together.

Question 17

Which of the following is a function of cholesterol in the cell membrane?

Accepted Answer

It helps regulate membrane fluidity and permeability.

Question 18

Which of the following best describes the structure of a nucleotide?

Accepted Answer

A nucleotide consists of a pentose sugar, a phosphate group, and a nitrogenous base.

Question 19

Which of the following best explains why phospholipids are essential for cell membrane structure?

Accepted Answer

They are amphipathic, with hydrophilic heads and hydrophobic tails, forming a bilayer.

Chemical Level of Organization: Study Notes for Anatomy & Physiology I

Study Guide - Practice Questions