Q: Calculate the molecular weight (MW) of glucose ($$C_6H_{12}O_6$) given the atomic weights: C = 12 amu, H = 1 amu, O = 16 amu.

$$MW = (6 \times 12) + (12 \times 1) + (6 \times 16) = 180$$ amu

Question 1

Which of the following statements best describes the difference between an atom and an element?

Accepted Answer

An element is a substance that cannot be broken down into simpler substances, while an atom is the smallest unit of matter that retains the chemical properties of that element.

Question 2

Which of the following elements makes up the largest percentage of the human body by weight?

Accepted Answer

Oxygen

Question 3

A radioactive isotope of iodine is administered to a patient to track thyroid hormone uptake. Which property of radioisotopes makes this possible?

Accepted Answer

Radioisotopes emit ionizing radiation that can be detected by imaging equipment.

Question 4

Which of the following best explains why water is an effective solvent for ionic compounds?

Accepted Answer

Water’s polar covalent bonds allow it to surround and separate ions, dissolving ionic compounds.

Question 5

Calculate the molecular weight (MW) of glucose ($$C_6H_{12}O_6$) given the atomic weights: C = 12 amu, H = 1 amu, O = 16 amu.

Accepted Answer

$$MW = (6 	imes 12) + (12 	imes 1) + (6 	imes 16) = 180$$ amu

Question 6

Which of the following best describes a buffer’s function in the human body?

Accepted Answer

A buffer resists changes in pH by neutralizing added acids or bases.

Question 7

A solution has a hydrogen ion concentration of $$[H^+] = 10$$^{-5}$$ M. What is its pH?

Accepted Answer

$$pH = -\log[10$$^{-5}$$] = 5$$

Question 8

Which type of chemical bond involves the sharing of electrons between atoms?

Accepted Answer

Covalent bond

Question 9

Which of the following is a correct example of a catabolic (decomposition) reaction?

Accepted Answer

$$AB \rightarrow A + B$$

Question 10

Which property of water allows it to absorb heat without a significant change in temperature?

Accepted Answer

High specific heat capacity

Question 11

Which of the following best describes the difference between a molecule and a compound?

Accepted Answer

A molecule is two or more atoms chemically bonded, while a compound is a molecule composed of two or more different types of atoms.

Question 12

Which of the following is a physiological role of electrolytes in the human body?

Accepted Answer

Electrolytes help maintain fluid balance, nerve function, and muscle contraction.

Question 13

Which of the following best explains why saturated fats are solid at room temperature while unsaturated fats are liquid?

Accepted Answer

Unsaturated fats have double bonds that create kinks, preventing tight packing.

Question 14

Which of the following is true regarding protein denaturation?

Accepted Answer

Denaturation disrupts hydrogen bonds and ionic interactions, destroying the protein’s shape and function.

Question 15

Which of the following is a correct description of ATP hydrolysis?

Accepted Answer

ATP hydrolysis is a catabolic reaction that releases energy for cellular work.

Question 16

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

Accepted Answer

Phospholipids are a major component of cell membranes, providing structural integrity and selective permeability.

Question 17

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

Accepted Answer

Enzymes lower activation energy, speeding up reactions without being consumed.

Question 18

Which of the following is a correct example of a reversible chemical reaction important in regulating blood pH?

Accepted Answer

$$CO_2 + H_2O$$ \rightleftharpoons H_2CO_3 \rightleftharpoons H^+ + $$HCO_3$$^-$$

Question 19

Which of the following best describes the relationship between monomers and polymers?

Accepted Answer

Polymers are large molecules made by linking together monomers through dehydration synthesis.

Chapter 2: The Chemistry of Life – Fundamental Principles for Anatomy & Physiology

Guida di studio - Domande di pratica

Study guide - Flashcard