Physiology - overview of respiratory system

Question 1

does gas exchange occur through type I or II alveolar cells

Answer 1

type I

Question 2

Type II alveolar cells function

Answer 2

secrete surfactant, reabsorb Na ions and water

Question 3

compliance definition

Answer 3

change in lung volume per change in transpulmonary pressure

Question 4

diseases associated with increased compliance

Answer 4

emphysema
hyperinflation of lungs
old age

Question 5

diseases associated with decreased compliance

Answer 5

pneumonia

pulmonary fibrosis

Question 6

surfactant effect on surface tension and compliance

Answer 6

reduce surface tension

increase compliance

Question 7

surfactant effect on hydrogen bonds in water molecules

Answer 7

reduces H bonds between water molecules

Question 8

RDS

Answer 8

respiratory distress syndrome

- absent/insufficient surfactant in premature babies causes RDS due to collapse of primitive alveoli

Question 9

Tidal volume

Answer 9

volume of gas inspired or expired in an unforced respiratory cycle

Question 10

residual volume

Answer 10

volume of gas in lungs after maximum expiration

Question 11

functional residual capacity

Answer 11

amount of gas in lungs after normal tidal expiration

Question 12

air in anatomical dead space has inc/dec CO2 and O2 concentration

Answer 12

increased CO2 concentration

decreased O2 concentration

Question 13

parasympathetic - broncho construction/dilation

Answer 13

bronchoconstriction

Question 14

sympathetic - broncho construction/dilation

Answer 14

bronchodilation

• decreased resistance
• increase air flow

Question 15

forces promoting alveolar collapse

Answer 15

elasticity
alveolar surface tension
- attraction between water molecules at liquid air surface

Question 16

forces keeping alveoli open

Answer 16

transmural pressure gradient
pulmonary surfactant
alveolar interdependence

Question 17

law of laplace

Answer 17

pressure is proportional to surface tension and inversely proportional to alveolar radius

Question 18

boyle’s law

Answer 18

pressure is inversely proportional to volume

Question 19

henry’s law

Answer 19

concentration of gas dissolved in a liquid is proportional to partial pressure of gas

Question 20

dalton’s law

Answer 20

pressire exerted by a gas mixture equals the sum of pressures that would be exerted by each gas alone

Question 21

2 factors in linkage of lungs to thorax

Answer 21

intrapleural fluid cohesiveness
- water molecules in intrapleural fluid are attracted together, resist pulling apart

negative intrapleural pressure
- lungs expand out, chest in