Question 1

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

Accepted Answer

Water has an uneven distribution of electrons, resulting in a partial negative charge ($$\delta^-) $$near oxygen and a partial positive charge ($$\delta^+) $$near hydrogen.

Question 2

A patient is suffering from muscle cramps and irregular heartbeat. Blood tests reveal low potassium levels. Which ion is most directly responsible for maintaining membrane potentials in muscle and nerve cells?

Accepted Answer

Potassium ($$\mathrm{K^+})$$

Question 3

Which of the following statements about acids and bases is correct?

Accepted Answer

Acids are proton donors and decrease the pH of a solution.

Question 4

A solution has a pH of 5. Which of the following is true about this solution?

Accepted Answer

It is acidic and contains more hydrogen ions than base ions.

Question 5

Which of the following best describes the function of buffers in biological systems?

Accepted Answer

Buffers prevent changes in pH when acids or bases are added.

Question 6

Which of the following is a correct representation of the dissociation of hydrochloric acid ($$\mathrm{HCl}) in $$water?

Accepted Answer

$$\mathrm{HCl} \rightarrow \mathrm{H^+} + \mathrm{Cl^-}$$

Question 7

Which of the following organic compounds is primarily used for energy storage in human muscle and liver cells?

Accepted Answer

Glycogen

Question 8

A triglyceride molecule is composed of:

Accepted Answer

Three fatty acids and one glycerol backbone

Question 9

Which type of fatty acid is associated with increased risk of heart disease due to its structure and dietary source?

Accepted Answer

Trans fats produced by hydrogenation of plant oils

Question 10

Phospholipids are essential components of cell membranes because:

Accepted Answer

They form a bilayer with hydrophilic heads facing the aqueous environment and hydrophobic tails facing inward.

Question 11

Which of the following is NOT a function of proteins in the human body?

Accepted Answer

Storing genetic information

Question 12

A patient with phenylketonuria (PKU) lacks the enzyme phenylalanine hydroxylase. What is the consequence of this deficiency?

Accepted Answer

Accumulation of phenylalanine leads to neurological damage if untreated.

Question 13

Which of the following best describes the structure of DNA?

Accepted Answer

A double-stranded helix with deoxyribose sugar and complementary base pairing.

Question 14

Which of the following is the correct formula for the hydrolysis of a disaccharide into two monosaccharides?

Accepted Answer

$$\mathrm{C$$_{12}$$H_{22}O$$_{11}} + \mathrm{H_2O} \rightarrow 2\mathrm{C_6H_{12}$$O_6$$}$

Question 15

Which of the following is a monomer of proteins?

Accepted Answer

Amino acid

Question 16

Which of the following best explains why enzymes are necessary for life?

Accepted Answer

Enzymes lower the activation energy ($$E_a) $$required for chemical reactions, allowing them to occur at body temperature.

Question 17

Which of the following correctly matches the organic compound with its function?

Accepted Answer

Nucleic acids: store and transmit genetic information

Question 18

A patient is diagnosed with scurvy due to vitamin C deficiency. Which protein's synthesis is most directly affected?

Accepted Answer

Collagen

Question 19

Which of the following is true about ATP (adenosine triphosphate)?

Accepted Answer

ATP stores chemical energy in its phosphate bonds and is synthesized from ADP and phosphate using energy from fuel oxidation.

Question 20

Which of the following best describes the difference between RNA and DNA?

Accepted Answer

RNA contains uracil instead of thymine and is single-stranded; DNA contains thymine and is double-stranded.

Chapter 2: The Chemistry of Life – Study Notes for Anatomy & Physiology

Guida di studio - Domande di pratica

Study guide - Flashcard