Human Gas Exchange System

Question 1

What is the surface of the lungs called?

Answer 1

alveolar epithelium

Question 2

How are the alveolar epithelium adapted to gas exchange?

Answer 2

having a large surface area, good blood supply, thin walls & elastic fibers which help recoil

Question 3

Define ventilation

Answer 3

Ventilation is the process of breathing in (inspiration) and out (expiration).

Question 4

Describe human Inspiration

Answer 4

1. external intercostal
muscles contract, 
2. rib cage moves
up & out, 
3. diaphragm contracts,
4. volume of the thorax is increased,
5. atmospheric pressure is greater than pulmonary pressure and air is
forced into the lungs.

Question 5

Describe human expiration

Answer 5

1. internal intercostal muscles contract,
2. ribs move down and inwards,
3. diaphragm relaxes,
4. volume of the thorax is decreased,
5. pulmonary pressure is greater than atmospheric
   pressure, air is forced out of the lungs

Question 6

What does a spirometer do?

Answer 6

measure the volume and function of the lungs

Question 7

How does a spirometer work?

Answer 7

Inhalation and expiration moves the lid of the spirometer which is recorded by the datalogger. Carbon dioxide is absorbed by soda lime in the chamber

Question 8

Define vital capacity

Answer 8

the maximum amount of air that can be moved by the lungs in one

Question 9

Define residual volume

Answer 9

the volume of air left
in the lungs after a
forced expiration

Question 10

Define tidal volume

Answer 10

the volume of air moved in and out of the lungs with a normal breath

Question 11

Describe movement of air in the thorax

Answer 11

trachea
broncos
bronchioles
alveoli

Question 12

Air movement in thorax diagram

Answer 12

see picture

Question 13

Thorax and abdomen diagram

Answer 13

see diagram