GAS EXCHANGE Flashcards
1
Q
How are alveoli adapted for gas exchange?
A
Permeable capillary wall
Flowing blood maintains high conc. gradient
1 cell thick capillary wall - decreases diffusion distance
Large surface area
Moist lining for gases to dissolve in
2
Q
How does gas exchange work in the alveoli?
A
There is more oxygen in the alveoli than the blood
There is more CO2 in the blood than the alveoli
Diffusion occurs from the areas of high to low concentrations
3
Q
How does the diaphragm work while exhaling?
A
It relaxes and moves up, becoming dome shaped
The volume decreases, increasing pressue
4
Q
(Unrelated to gas exchange) - How does food go down the oesophagus?
A
Peristalsis
Waves of muscle contractions
