P1 15. Gaseous Exchange Flashcards
gaseous exchange for oxygen and carbon dioxide?
oxygen moves from the air into the alveoli the blood in the capillaries carbon dioxide moves from the blood into the capillaries into the air in the alveoli
capillaries characteristics recap
Meshlike wrapped around muscles and organs
Lots of different capillaries in each mesh
Each capillary is very narrow, where blood cells have to travel through one at a time
Capillaries have wolves, which are one cell thick to allow gases to diffuse through into muscles and organs
What happens during gaseous exchange?
inhaled oxygen
Oxygen into the alveoli by diffusion
The blood contains oxygen to go to the muscles and organs
DeOxygenated blood carrying carbon dioxide returns to the capillaries
Diffusion in the alveoli
Exhaling carbon dioxide
What is diffusion?
Diffusion describes how molecules move from an area of high concentration to an area of low concentration in attempt to reach a balance
what happens to oxygen once you have inhaled?
High concentration of oxygen in the alveoli as a result, oxygen diffuse into the blood
what happens to carbon dioxide once you have inhaled?
Concentration of carbon dioxide in the blood compared to the capillaries, then there is in the air of the alveoli capillaries into the air in the alveoli, which is taken out of the lungs
Alveoli facts
there are around 400 million alveoli in your lungs, providing a massive surface for diffusion
capillaries and alveoli are very closely wrapped together, so they only have to diffuse short distance
The blood supply to alveoli is substantial lots of gas is carried away quickly
Alveoli have moist, thin walls, perfect gases exchange to diffuse through
what is diffusion
gaseous exchange is the diffusion of gases in opposite directions at the same time. This means the oxygen diffuses into the blood in the capillaries at the same time as carbon dioxide diffuses into the air in the alveoli.
what happens to gaseous exchange during exercise
during exercise the muscles use more oxygen
as a result the blood returning from the muscles has lower the normal concentration of oxygen
because the concentration in the blood, and in the air in the alveoli is greater into the blood
what happens to carbon dioxide during gas exchange during exercise?
at the same time more carbon dioxide is created in the Muscles during exercise
as a result of the higher carbon dioxide in the blood and the greater difference between this and the concentration of carbon dioxide in the air of the alveoli more carbon dioxide is diffused into the air in the alveoli
