Chapter 29 Structure and Function of the Respiratory System

Question 1

Ventilation
Perfusion
Diffusion (resp)

Answer 1

Ventilation is the movement of air between atmosphere and lungs
Perfusion is the flow of blood through the lungs
Diffusion is the transfer of gases between air-filled spaces in the lungs (alveoli).

Question 2

Right lung Vs Left lung

Answer 2

Right lung has three lobes. The right main bronchus is short, wider, and more vertical than the one in the left.

Question 3

Larynx
- Location
- AKA
- Function

Answer 3

• Passageway that connects the oropharynx with the trachea.
• Voicebox
• Produces speech and protects the lungs from airborne irritants

Question 4

Pharynx
- Location

Answer 4

Back of throat. The passage that connects the nares and throat to the trachea which connects to the lungs.

Question 5

What are alveoli? Why are they important? Type 1 VS type 2 alveolar cells

Answer 5

Tiny, air-filled sacs located in the lungs. Site of gas exchange.

Type 1 alveolar cells are flat squamous epithelial cells where gas exchange takes place.

Type 2 alveolar cells produce surfactant. A lipoprotein that decreases surface tension in the alveoli allowing for easier lung inflation.

Question 6

Alveolar Macrophages
- TB

Answer 6

These are macrophages that live in the alveoli. They phagocytize pathogens and debris. When Mycobacterium tuberculosis is phagocytized, it creates an insoluble capsule that will contain the bacteria until the host’s immune system declines when it can then remerge.

Question 7

What is bronchial circulation? How does it differ from pulmonary circulation?

Answer 7

Bronchial circulation stems from the thoracic aorta. It supplies oxygen and nutrients to the lung tissues. It also works to warm and humidify incoming air.

Pulmonary circulation provides gas exchange for the entire body. Through the pulmonary artery.

Question 8

Lung compliance
- Equation
- What is it?

Answer 8

Lung compliance = volume of the lungs / pressure in the lungs

Stretch of the lungs to accommodate air in, air out. Also different amounts of air at different times.

Question 9

Tidal Volume (Vt)

Answer 9

Amount of air that moves in and out of the lungs during a normal breath

Question 10

Inspiratory Reserve Volume

Answer 10

Maximum amount of air that can be inspired in excess of the normal Vt

Question 11

Vital capacity

Answer 11

Amount of air that can be exhaled from the point of maximal inspiration

Question 12

Dead space
- Anatomic
- Alveolar

Answer 12

Area of the pulmonary system that does not participate in gas exchange.
- Anatomic - the portion of the conducting airways that does not participate in gas exchange
- Alveolar - the portion of the lung that does not participate in gas exchange

Question 13

What is a shunt?

Physiologic shunt

Answer 13

Movement of blood from the venous to the arterial side of circulation without moving through the lungs (becoming oxygenated).

A shunt that results due to a ventilation and perfusion mismatch. For example, the patient is ventilating just fine, however, there is a portion of one of the lungs that has suffered an infarct. This decreases the perfusion there, making a mismatch.

Question 14

What is PO2? What is the normal value?

Answer 14

Partial pressure of oxygen. Measured via ABG. Should be 80mmHg or greater.

Question 15

What is PCO2? What is the normal values?

Answer 15

Partial pressure of carbon dioxide. A measurement on ABG. Should be 35-45mmHg. Higher PCO2 levels indicate respiratory acidosis or attempt to compensate for metabolic alkalosis.

Question 16

Chemoreceptors and lung receptors

Answer 16

Chemoreceptors monitor blood oxygen levels and carbon dioxide levels are adjust ventilation to meet the changing metabolic needs of the body.
Lung receptors monitor breathing patterns and lung function.