VII. Respiratory System

Question 1

Functions of Respiratory System

Answer 1

O2 and CO2 exchange between blood and air
Speech
Smell
Acid/base regulation

Question 2

Ventilation

Answer 2

Flow of air in and out of lungs

Question 3

Movement of air

Answer 3

High pressure -> low pressure

Question 4

Boyle’s law

Answer 4

Pressure of gas varies inversely to volume (compress = pressure up)

Question 5

Inspiration Process

Answer 5

Thorax enlarges
Pressure drops
Air moves in

Question 6

Expiration Process

Answer 6

Thorax gets smaller
Pressure rises
Air moves out

Question 7

Muscles involved in INSPIRATION

Answer 7

Diaphragm
External Intercostals
Sternocleidomastoids
Scalenes
Pectoralis Minor

Question 8

Muscles involved in normal EXPIRATION

Answer 8

Trick question - it’s passive - they relax

Question 9

Muscles involved in active EXPIRATION

Answer 9

Internatl Intercostals
External Oblique
Internal Oblique
Transversus Abdominis
Rectus Abdominis

Question 10

Air pressures (3)

Answer 10

Intrapleural
Air
Intrapulmonary

Question 11

Intrapleural Pressure

Answer 11

Space between parietal pleura and visceral pleura - always below atmospheric or intrapulmonary pressures - always slightly inflated

Question 12

Pneumothroax

Answer 12

Presence of air in pleural cavity - collapses lungs!

Question 13

Atmospheric pressure

Answer 13

760 mmHg

Question 14

Pressure -lungs and thorax at rest

Answer 14

Air - 760 mmHg
Intrapleural 756 mmHg
Intrapulmonary 760mmHg
Air doesn’t move

Question 15

Surfactant

Answer 15

Reduces surface tension inside alveoli

Concentrated when lungs are uninflated, reduces tension
Spreads when lungs are inflated

Question 16

Lung compliance

Answer 16

ability of lungs to expand - depends on surface tension and elasticity of lungs
Inversely related to elastic recoil

Question 17

How is fetal hemoglobin different from adult

Answer 17

It can bind oxygen with greater affinity - allowing the fetus better access to the mother’s oxygen