Gaseous Exchange

Question 1

Definition of gas exchange

Answer 1

Passive process that occurs via diffusion

Question 2

What are the different concentrations of oxygen and carbon dioxide within the alveoli and the lungs?

Answer 2

High concentration of oxygen in the lungs and low in the capillaries.
High concentration of carbon dioxide in the capillaries and low concentration in the aveoli

Question 3

How is the alveolus adapted for diffusion?

Answer 3

Large surface area to volume ratio
Moist
Many capillaries surround it so there is a short diffusion distance

Question 4

How are capillaries adapted for diffusion?

Answer 4

1 cell thick with semi permeable membrane
Short diffusion pathway
Moist
Rich blood supply

Question 5

Give facts about haemoglobin

Answer 5

Carry up to four oxygen molecules at a time
When it is full it is called being fully saturated
When oxygen attaches to it it forms oxyhaemoglobin

Question 6

Describe the difference between gaseous exchange at rest and exercise

Answer 6

Oxygen and carbon dioxide is low at rest and high at exercise
Shallow concentration gradient at rest and steep during exercise (gaseous exchange is more efficient)

Question 7

What are the different types of lung volumes?

Answer 7

Tidal-Amount of air breathed in and out at rest
Residual- Air that remains in lungs after maximal expiration. Stops lungs collapsing
Inspiratory Reserve- additional air that can be forcibly inhaled after inspiration of normal tidal volume
Expiratory Reserve-Forcibly exhaled after expiration of a normal tidal volume

Question 8

What happens to tidal volume during exercise?

Answer 8

Tidal volume gets taller and closer together on a graph because during exercise our breathing becomes deeper and more frequent