Gas exchange Flashcards
How does oxygen get into a cell?
Diffusion
Why do larger animals need to have a respiratory and circulatory system to get enough oxygen?
Diffusion doesn’t work very well over long distances, so a respiratory system is needed to extract oxygen and the circulatory system moves it around
Gases dissolve, diffuse, and react according to what?
Their pressure
What does Henry’s Law describe?
How gases dissolve in liquids
Which law is Henry’s law a modification of?
The ideal gas law
Why is gas solubility important?
Gases need to be dissolved to diffuse into a cell
What determines the amount of gas that dissolves in a liquid?
The solubility of a gas and the partial pressure of that gas
What is the absorption coefficient?
A measure of gas solubility
What is a temperature effect?
As temperature increases, gas solubility decreases
What is the ion effect?
As ion concentration increases, gas solubility decreases
How do the solubilities of oxygen, nitrogen and carbon dioxide compare to each other?
CO2 is more soluble than O2 and N2
What does the Fick equation describe?
The rate of diffusion in mol/s
What is the diffusion coefficient?
How well a substance moves through a specific medium
How will respiratory system anatomy facilitate oxygen diffusion to cells?
The anatomy will be the system that can best extract oxygen from the environment of the animal
What are the 3 major strategies for general gas exchange?
- Circulating the external medium through the body
- Diffusion across the body surface with an internal circulatory system
- Diffusion across specialized respiratory membrane with an internal circulatory system
