Question 1

Which of the following is NOT one of the four attributes required for effective respiratory gas exchange?

Accepted Answer

The exchange region must have a large concentration gradient for the gas.

Question 2

Which mechanism of gas exchange is primarily used by single-celled organisms such as amoebas?

Accepted Answer

Integumentary exchange (diffusion across the body surface)

Question 3

Why is gas exchange generally less efficient in water than in air?

Accepted Answer

Oxygen concentration is lower in water than in air.

Question 4

Which evolutionary adaptation allowed tetrapods to successfully colonize land?

Accepted Answer

Evolution of lungs

Question 5

In insects, what is the primary function of spiracles in the tracheal system?

Accepted Answer

To allow air to enter and exit the tracheal tubes

Question 6

Which of the following best describes the path of air flow in the human respiratory system?

Accepted Answer

Nasal cavity → Pharynx → Trachea → Bronchi → Bronchioles → Alveoli

Question 7

Which structure in the human respiratory tract is lined with pseudo-stratified columnar epithelium and functions as a ciliary elevator?

Accepted Answer

Trachea

Question 8

Negative pressure breathing in humans is primarily achieved by which muscle?

Accepted Answer

Diaphragm

Question 9

Birds have a unique respiratory system compared to humans. Which statement best describes this difference?

Accepted Answer

Birds have air sacs and a one-way (cross-current) ventilation system.

Question 10

Which equation correctly represents the conversion of carbon dioxide to bicarbonate in the blood?

Accepted Answer

$$\mathrm{CO_2$} + \mathrm{H_2O} \rightarrow \mathrm{H_2CO_3} \rightarrow \mathrm{$$HCO_3$$^-} + \mathrm{H^+}$$

Question 11

Hemoglobin binds oxygen cooperatively. What does this mean?

Accepted Answer

Binding of one oxygen molecule increases the affinity for the next oxygen molecule.

Question 12

Which of the following is NOT a way that carbon dioxide is transported in the blood?

Accepted Answer

Bound to plasma proteins as carboxylate

Question 13

During pregnancy, how does the human fetus exchange gases with the mother's blood?

Accepted Answer

Via the placenta, where fetal and maternal blood exchange gases without mixing

Question 14

Which of the following best explains why alveoli are highly adapted for gas exchange?

Accepted Answer

They are surrounded by capillary beds and have a large surface area.

Question 15

If a person’s tidal volume is 500 mL and their respiratory rate is 12 breaths per minute, what is their minute ventilation?

Accepted Answer

$$500 \ \mathrm{mL} 	imes 12 = 6000 \ \mathrm{mL/min}$$

Question 16

Which pressure gradient drives the diffusion of oxygen from alveoli into the blood?

Accepted Answer

Oxygen moves from high partial pressure in alveoli to low partial pressure in blood.

Question 17

Which of the following respiratory organ systems is most efficient for gas exchange in aquatic environments?

Accepted Answer

Gills

Question 18

A patient is exposed to carbon monoxide (CO). Why is this dangerous in terms of hemoglobin function?

Accepted Answer

CO binds to hemoglobin at the same site as oxygen, preventing oxygen binding.

Question 19

Which of the following statements about the control of breathing is correct?

Accepted Answer

Breathing is automatically regulated by centers in the brainstem.

Question 20

Which of the following is a multi-step process that occurs during exhalation in negative pressure breathing?

Accepted Answer

The diaphragm relaxes, thoracic cavity volume decreases, and air is expelled.

Chapter 30: The Respiratory System and Gas Exchange

Study Guide - Practice Questions