Respiratory System

Question 1

Which of the following is happening during a contraction of the diaphragm?

A decrease in alveolar pressure
A decrease in the volume of the thoracic cavity
Forced expiration
An increase in alveolar pressure

Answer 1

A decrease in alveolar pressure

Extra:
When the diaphragm is contracting, it is moving downward and allowing the lungs to inflate. During inhalation, alveolar pressure is decreased because the expansion of the lungs increases the surface area or number of alveoli available for gas exchange, thus reducing the pressure at the alveoli.

Question 2

The ______________ is a double layered membrane that lines the lungs.

pleura
pleural cavity
pericardium
alveolus

Answer 2

pleura

Question 3

Which of the following lists the respiratory passageways in order from largest diameter to smallest diameter?

Bronchioles, bronchi, trachea
Bronchi, trachea, bronchioles
Trachea, bronchi, bronchioles
Trachea, bronchioles, bronchi

Answer 3

Trachea, bronchi, bronchioles

Question 4

Which of the following terms is alternatively called the “voice box”?

Larynx
Trachea
Uvula
Pharynx

Answer 4

Larynx

Question 5

Which of the following best describes the mechanical process of normal breathing during expiration(exhaling)?

The diaphragm relaxes and moves upward, while the intercostal muscles contract and move the ribs upward.
The diaphragm contracts and moves upward, while the intercostal muscles relax and contract upward.
The diaphragm relaxes and moves upward, while the intercostal muscles relax and move the ribs downward.
The diaphragm relaxes and moves downward, while the intercostal muscles relax and move the ribs downward.

Answer 5

The diaphragm relaxes and moves upward, while the intercostal muscles relax and move the ribs downward.

Extra:
During exhalation, two primary components drive the mechanical process- the diaphragm and the intercostal muscles. During inhalation, the lungs fill with air with the help of the intercostal muscles moving up and outward to expand the chest cavity. The diaphragm contracts and pushes downward to make room for the expanded lungs.

During expiration, the opposite movements occur in order to help push air out of the lungs. Thus during exhalation, the diaphragm moves up and the intercostal muscles move the ribs downward.

Question 6

Gas exchange between the blood and alveoli would be enhanced by ______________, but impeded by __________________.

increased tidal volume; decreased membrane thickness
increased alveolar surface area; increased membrane thickness
decreased membrane thickness; increased alveolar surface area
decreased respiratory rate; increased tidal volume

Answer 6

increased alveolar surface area; increased membrane thickness

Question 7

In the respiratory system, the majority of gas exchange takes place ___________________.

in the alveoli
in the trachea
in the bronchioles
in the bronchi

Answer 7

in the alveoli

Question 8

Which of the following describes the volume of air associated with a normal breath?

Total lung capacity
Residual volume
Tidal volume
Inspiratory reserve volume

Answer 8

Tidal Vol.

Question 9

Which of the following conditions would exhibit an increase in lung compliance?

Bronchitis
Lung cancer
Emphysema
Asthma

Answer 9

Emphysema

Question 10

Which of the following substances is produced by the lung for the purpose of reducing surface tension?

Carbon dioxide
Sodium bicarbonate
Oxidase
Surfactant

Answer 10

Surfactant

Question 11

As air is inhaled, the sequence in which it passes through the respiratory tract is best described by which of the following choices?

Nasal cavity, trachea, pharynx, larynx, bronchioles, bronchi
Pharynx, nasal cavity, larynx, trachea, bronchi, bronchioles
Nasal cavity, bronchi, bronchioles, trachea, pharynx, larynx
Nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles

Answer 11

Nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles

Question 12

______________ is the exchange of oxygen and carbon dioxide across the alveolar membrane.

Osmosis
Diffusion
Active transport
Exocytosis

Answer 12

Diffusion

Question 13

Which of the following anatomical structures prevents food from entering the respiratory system?

Pharynx
Pleura
Epiglottis
Larynx

Answer 13

Epiglottis

Question 14

Which of the following terms correctly describes the movement of air in and out of the lungs?

 Ventilation
 Diffusion
 Oxidation
 Respiration
Incorrect

Answer 14

Ventilation

Extra:
Ventilation is the physical movement of air in and out of the lungs.

Respiration is the use of oxygen by a cell or organism to make energy.

Oxidation refers to a chemical process in which a molecule loses electrons.

Diffusion is the passive movement of a substance from high concentration to low concentration.

Question 15

Voluntarily holding your breath will eventually result in:

an innate reflex to start breathing due to low oxygen levels.
brain damage or death to due to lack of oxygen.
temporary unconsciousness and risk of stroke.
an innate reflex to start breathing due to increased carbon dioxide levels.

Answer 15

an innate reflex to start breathing due to increased carbon dioxide levels.

Question 16

A lung with a low level of compliance could be best described as _____________.

A lung with a high elasticity but with damaged alveoli.
a highly elastic lung allowing breathing occur with reduced work.
a stiff lung requiring extra work to accomplish normal breathing.
a lung with normal function.

Answer 16

a stiff lung requiring extra work to accomplish normal breathing.

Question 17

Which of the following is not a function of pulmonary surfactant?

Decrease in lung compliance
Prevention of lung collapse
Reduction of surface tension
Increase in lung compliance

Answer 17

Decrease in lung compliance

Extra:
The purpose of surfactant is to prevent lung collapse and to reduce surface tension. Additionally, it increases the compliance of the lung, meaning it can inflate more easily.

A decrease in lung compliance would make it more difficult to inflate the lungs. This is the opposite effect of surfactant.