Gas Exchange In Humans

Question 1

What is the process of inspiration

Answer 1

↳ Between the ribs
Ribcage moves up and outwards providing a larger volume in the thorac
Diaphragm contracts (downwards from dome position)
Decrease in the pressure of the lungs but as air moves in it rises above atm
lung volume increases to decrease pressure
Air moves into the lungs from atm pressure into lower pressure

Question 2

What is the process of expiration

Answer 2

~External intercostal muscle relasses
Internal intercostal muscle contracts pulling ribs downwards and inward,
~ Diaphragm relaxes returning to domed position
Air pressure in lungs is initially greater than atm. Drops as air moves out
lung volume decreases to increase pressure
<Air moves out of lungs from high pressure in lungs out to atm pressure

Question 3

Adaptations of alveolar epithelium

Answer 3

Gas exchange occurs between the epithelium and the blood
large surface area -many in human lung (300 million
‘Alveoli epethelium cells are very thin to minimise diffusion distance
‘surrounded by a large network of cappitaries to remove exchanged gases and therefore maintains a concentration gradient

Question 4

What is the difference between breathing and respiration

Answer 4

Breathing: movement fair into and out of the lungs
Respiration: chemical reaction to release energy in the form of ATP

Question 5

What does antagonistic mean

Answer 5

-interaction between external& intercostal muscles