Q: A solution has a pH of 2. What is the concentration of hydrogen ions $$[H^+] in $$this solution?

$$[H^+] = 10$$^{-2}$$ \text{ M}$$

Q: Which of the following is the correct formula for calculating the number of neutrons in an atom?

$$\text{Number of neutrons} = \text{Mass number} - \text{Atomic number}$$

Question 1

Which of the following statements best describes the difference between organic and inorganic compounds in the human body?

Accepted Answer

Organic compounds always contain carbon and hydrogen, usually contain oxygen, and have covalent bonds; inorganic compounds usually lack carbon and are simple molecules.

Question 2

A neutral atom of sodium (Na) has an atomic number of 11 and a mass number of 23. How many neutrons does it have?

Accepted Answer

$$23 - 11 = 12$$

Question 3

Which type of chemical bond is formed when atoms share electrons?

Accepted Answer

Covalent bond

Question 4

A solution has a pH of 2. What is the concentration of hydrogen ions $$[H^+] in $$this solution?

Accepted Answer

$$[H^+] = 10$$^{-2}$$ 	ext{ M}$$

Question 5

Which property of phospholipids allows them to form bilayers in cell membranes?

Accepted Answer

They are amphipathic, having both hydrophilic heads and hydrophobic tails.

Question 6

Which of the following best explains why water is considered the most important and abundant inorganic compound in living things?

Accepted Answer

Water acts as a solvent, participates in chemical reactions, and helps regulate temperature.

Question 7

A patient’s blood pH drops to 7.10. Which of the following best describes this condition?

Accepted Answer

The patient is experiencing acidosis.

Question 8

Which of the following ions is most important for nerve impulse transmission in the human body?

Accepted Answer

K$$^{+} ($$potassium ion)

Question 9

Which process is responsible for breaking down polysaccharides into monosaccharides in the digestive system?

Accepted Answer

Hydrolysis

Question 10

Which of the following best describes the role of enzymes in biological systems?

Accepted Answer

Enzymes are biological catalysts that increase the speed of chemical reactions.

Question 11

A triglyceride is formed by the combination of which molecules?

Accepted Answer

One glycerol molecule and three fatty acids

Question 12

Which of the following is true about saturated fatty acids?

Accepted Answer

They contain only single bonds between carbon atoms.

Question 13

Which of the following best explains why proteins denature when exposed to high heat or extreme pH?

Accepted Answer

Heat and pH disrupt hydrogen and ionic bonds, altering the protein’s tertiary structure.

Question 14

Which of the following is the correct formula for calculating the number of neutrons in an atom?

Accepted Answer

$$	ext{Number of neutrons} = 	ext{Mass number} - 	ext{Atomic number}$$

Question 15

Which of the following best describes the structure of DNA?

Accepted Answer

DNA is a double-stranded molecule containing thymine.

Question 16

Which of the following is a function of cholesterol in the body?

Accepted Answer

It is a precursor for steroid hormones and vitamin D.

Question 17

Which of the following best explains why unsaturated fatty acids are less likely to clog blood vessels than saturated fatty acids?

Accepted Answer

Unsaturated fatty acids have double bonds that create kinks, making them less likely to pack tightly and form solids.

Question 18

Which of the following best describes the role of ATP in cells?

Accepted Answer

ATP is the principal energy-storing molecule in the body.

Question 19

Which of the following is an example of a buffer in the human body, and what is its function?

Accepted Answer

Bicarbonate; it resists changes in blood pH by neutralizing excess acids or bases.

Question 20

Which of the following best describes the difference between a polar covalent bond and a nonpolar covalent bond?

Accepted Answer

Polar covalent bonds involve unequal sharing of electrons, resulting in partial charges; nonpolar covalent bonds involve equal sharing of electrons.

Chapter 2: The Chemical Level of Organization – Principles of Anatomy and Physiology

Guida di studio - Domande di pratica

Study guide - Flashcard