Lecture 22: Pulmonary Ventilation and Gas Laws

Question 1

What muscles are inspiratory?

Answer 1

respiratory diaphragm
external intercostal muscles 
sternomastoids
serratus anterior muscles
scalene muscles

Question 2

What muscles are expiratory?

Answer 2

passive at rest (no muscles used)

forced expiration: abdominal muscles, internal intercostals

Question 3

What is total lung capacity?

Answer 3

maximum volume of gas the lungs can hold

Question 4

What is tidal volume?

Answer 4

500 ml

volume of air that is inspired or expired with each breath at rest

Question 5

What is the inspiratory reserve volume?

Answer 5

3000 ml

volume of air that can be inspired in addition to tidal volume with forceful inspiration

Question 6

What is the expiratory reserve volume?

Answer 6

1100 ml

additional volume of air that can be expired at end of tidal volume by forceful expiration

Question 7

What is residual volume?

Answer 7

1200 ml

volume of air remaining in lungs after forceful expiration

Question 8

What is vital capacity?

Answer 8

4600 ml
sum of all the volumes that can be inspired or exhaled, inspiration to maximum extent plus expiration to the maximum extent

Question 9

What is total lung capacity?

Answer 9

5800 ml

sum of all the volumes= vital capacity plus residual volume

Question 10

What is inspiratory capacity?

Answer 10

3500 ml

sum of volumes above resting capacity= tidal volume plus inspiratory reserve volume

Question 11

What is functional residual capacity?

Answer 11

2300 ml

sum of volumes below resting capacity = expiratory reserve volume + residual volume

Question 12

What is minute ventilation?

Answer 12

total volume of gases moved into or out of the lungs per minute

Question 13

How is minute ventilation calculated?

Answer 13

breaths per minute x tidal volume

Question 14

What is alveolar ventilation?

Answer 14

total volume of gases that enter spaces participating in gas exchange

Question 15

How is alveolar ventilation calculated?

Answer 15

breaths per minute x (tidal volume - dead space)

Question 16

What is anatomical dead space?

Answer 16

trachea, bronchi, bronchioles

Question 17

What is physiological dead space?

Answer 17

anatomic dead space + ventilated alveoli with poor or absent perfusion

Question 18

What is the total dead space in an individual?

Answer 18

.15 liters

Question 19

Minute ventilation = ____ x breathing rate

Answer 19

.5

Question 20

Alveolar ventilation = ____ x breathing rate

Answer 20

.35

Question 21

What does dead space not participate in?

Answer 21

gas exchange

Question 22

What is pleural pressure?

Answer 22

pressure of the fluid between parietal pleura and the visceral pleura

Question 23

What is alveolar pressure?

Answer 23

pressure of the air inside the alveoli

Question 24

What is trans pulmonary pressure?

Answer 24

difference between the alveolar pressure and the pleural pressure

Question 25

What is compliance?

Answer 25

the extent (volume) to which lungs will expand for each unit increase in the transpulmonary pressure

Question 26

What is the compliance equation?

Answer 26

increase in volume / increase in pressure or distensibility x volume

Question 27

What is elastance?

Answer 27

measure of the tendency of a hollow virus recoil toward original dimensions

Question 28

What are the most important components of surfactant?

Answer 28

dipalmitoylphophatidylcholine (a phospholipid) surfactant apoproteins calcium ions

Question 29

pressure = 2 x _______ / _______

Answer 29

surface tension; radius of alveolus

Question 30

If there is no surfactant, the pressure would calculate to about ____ cm of water pressure, about ___ times as great

Answer 30

18; 4.5

Question 31

What makes up atmospheric pressure?

Answer 31

78.09% N 20.95% O2 .93% Ar 0.03% CO2

Question 32

What is Dalton's law?

Answer 32

total pressure exerted by the mixture of non reactive gases equal to the sum of the partial pressures of individual gases

Question 33

What is Boyle's law?

Answer 33

for a fixed amount of an ideal gas kept at a fixed temperature, P (pressure) and V (volume) are inversely proportional

Question 34

What is Henry's law?

Answer 34

at a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of the gas in equilibrium with that liquid

Question 35

What is the ideal gas law?

Answer 35

P = nRT/ V

Question 36

What is the partial pressure of O2 at alveolar membrane?

Answer 36

150 mmHg

Question 37

What is the partial pressure of CO2 at alveolar membrane?

Answer 37

0.21 mmHg

Question 38

What are the factors that affect rate of gas diffusion in a fluid?

Answer 38

``` solubility of gas in the fluid cross sectional area of the fluid distance through which the gas must diffuse molecular weight of gas temperature of fluid ```