Respiratory Systen II

Question 1

What is hypoxia

Answer 1

Shortage of oxygen in the body

Question 2

True or false
During hypoxia vascoconstriction in areas with lower partially pressure for oxygen and blood is redirected

Answer 2

True

Question 3

Lung blood volume is equally to??

Answer 3

450 ml which is 9% of total blood volume

Question 4

Pulmonary capillary blood volume is equally to?

Answer 4

70 ml

Question 5

The rest of 380 ml blood is distributed across where?

Answer 5

Pulmonary arteries and veins

Question 6

What happen when the is a decrease in PO2

Answer 6

Adjacent blood vessels constrict
Increased vascular resistance
Decreased blood flow

Question 7

Name of receptors detecting amount of oxygen in the blood

Answer 7

Chemoreceptors

Question 8

Explain the blood flow during exercise

Answer 8

The blood flow increases because of vaporization of arteries results increase in blood flow carrying oxygen to the tissues per unit time
In addition the enhance blood flow increases microvessels hematocrit, which also supports increased oxygen delivery to tissues

Question 9

What is happening at zone 1

Answer 9

No blood flow during all portion of cardiac cycle because the local alveolar capillary pressure in that area of the lung never rises higher than alveolar air pressure during any part of cardiac cycle
Alveolar air pressure > pulmonary capillary pressure
No blood flow

Question 10

What is happening at zone 2

Answer 10

Intermittent blood flow only during the peaks of pulmonary arterial pressure because the systolic pressure is then greater than the alveolar air pressure but diastolic pressure is less than the alveolar air pressure
Systolic Ppc> alveolar air pressure> diastolic pulmonary capillary pressure

Question 11

What is happening at zone 3

Answer 11

Pulmonary capillary pressure > Alveolar air pressure
Continous flow

Question 12

List the partially pressure for forces tending to cause movement of fluid outward from the capillaries and into the pulmonary interstitium

Answer 12

Capillary pressure 7
Interstitial fluid colloid osmotic pressure 14
Negative Interstitial fluid pressure 8
Total outward forces 29

Question 13

List the forces tending to cause absorption of fluid into capillaries

Answer 13

Plasma colloid osmotic pressure 28

Question 14

List the composition of alveolar air and atmospheric air

Answer 14

Atmospheric air
N2- 597
O2-159
CO2-0.3
H2O- 3.7

Alveolar air
N2-569
O2-104
CO2-40
H20-47

Question 15

Partial pressure of oxygen and carbon dioxide in dry air

Answer 15

Oxygen- 160 mmHg
Carbon dioxide- 0.025

Question 16

Partial pressure for alveoli, arterial, cells, venous

Answer 16

Alveoli-
O2- 100
CO2- 40

Arterial blood
O2- 100
CO2- 40

Cells
CO2- 46
O2- 40

Venous
O2- 40
CO2- 46

Question 17

Name the structures where oxygen will pass through when diffusing from alveolus to capillary

Answer 17

1. Fluid and surfactant layer
2. Alveolar epithelium
3. Epithelium basement membrane
4. Interstitial space
5. Capillary basement membrane
6. Capillary endothelial membrane

Question 18

Factors affecting rate of diffusion across the respiratory membrane

Answer 18

A. Thickness of the membrane
Fluid accumulation in the interstitial space and alveolar, lung fibrosis
Increase in thickness
B. surface are of the membrane
Emphysema, removal of a lung
Decrease surface area
C. Diffusion coefficient of individual gases
Gas’s solubility
D. Partial pressure difference
Difference in Pa of the gases between alveoli and pulmonary capillaries

Question 19

What is Diffusing capacity

Answer 19

Ability of the respiratory membrane to allow for gaseous exchange between alveoli and pulmonary capillary
Volume of gas that will diffuse through the membrane each minute for a partial pressure of 1 mmHg