Respiration During Exercise Part 1 W7

Question 1

What is the primary purpose of the respiratory system?

Answer 1

To maintain arterial blood-gas homeostasis

Question 2

What 4 step process allows the respiratory system to maintain arterial blood-gas homeostasis?

Answer 2

1) Pulmonary ventilation
2) Alveolar gas exchange
3) Gas Transport
4) Systemic gas exchange

Question 3

What is the epiglottis?

Answer 3

Separates upper and lower respiratory tracts

Question 4

What is pleura?

Answer 4

Membranes enclosing the lungs

Question 5

What is greater, intrapleural pressure or atmospheric pressure?

Answer 5

Atmospheric as intrapleural pressure is always lower to allow the lungs to stay inflated and prevent alveoli from collapsing

Question 6

How many airway generations are there?

Answer 6

23

Question 7

What is the main bronchi?

Answer 7

Z1 extending to the terminal bronchioles (Z16)

Question 8

Where does gas exchange occur?

Answer 8

In the respiratory zone (Z17-23)

Question 9

Where does pulmonary gas exchange occur?

Answer 9

Across the pulmonary capillary

Question 10

What are alveolar cells called?

Answer 10

Pneumocytes

Question 11

What are Type I cells (alveolar) like?

Answer 11

Cover 95% of the internal surface of the alveolus and are critical for gas exchange

Question 12

What are Type II cells (alveolar) like?

Answer 12

They release surfactant

Question 13

What is a surfactant?

Answer 13

A molecule that lowers the surface tension

Question 14

What is the volume of gas passing though a sheet dependent on? (4)

Answer 14

1) Surface Area
2) Thickness
3) Diffusion Coefficient
4) Pressure Gradient (Alveolar to Arterial)

Question 15

What are the 5 layers that are involves the diffusion path from alveolar gas to the erythrocyte?

Answer 15

1) Surfactant
2) Alveolar epithelium
3) Interstitium
4) Capillary endothelium
5) Plasma

Question 16

What is the mechanics of breathing?

Answer 16

They are concerned with the movement of air into and out of the lungs by changes in pressure, flow and volume

Question 17

How does inspiration happen?

Answer 17

The thoracic cavity increases as respiratory muscles contract

Question 18

What is the vertical change of the thoracic cavity during inspiration?

Answer 18

Diaphragm contracts: vertical dimension of the thoracic cavity increase

Question 19

What is the lateral change of the thoracic cavity during inspiration?

Answer 19

Rib are elevated and thoracic cavity widens

Question 20

What is the anterior-posterior change of the thoracic cavity during inspiration?

Answer 20

Inferior portion of the sternum moves anteriorly and thoracic cavity expands

Question 21

What is bilateral phrenic nerve stimulation?

Answer 21

A non-volitational measure of diaphragmatic fatigue

Question 22

What is Ohm’s law?

Answer 22

Current= voltage/resistance

Question 23

In Ohm’s law, what is airflow dependent upon?

Answer 23

Pressure gradient and airway resistance

Question 24

What is Poiseuille’s Law?

Answer 24

Dependent upon length and radius of a tube

Question 25

What is the major determinant of airway resistance?

Answer 25

Radius (raised to the fourth power)

Question 26

What is the dead space>

Answer 26

The volume of air not participating in gas exchange

Question 27

What is pulmonary volume (on a graph)?

Answer 27

1 segment

Question 28

What is pulmonary capacity (on a graph)?

Answer 28

2 or more segments

Question 29

What is resistance to airflow mainly determined by?

Answer 29

Airway diameter

Question 30

What is forced vital capacity (FVC)?

Answer 30

The maximum volume air that can be forcefully expired after a maximum inspiration

Question 31

How is COPD characterised?

Answer 31

Increased airway resistance
Reduced FEV1/FVC