Diffusion is the movement of a substance across a semi permeable membrane from an area of high to an area of low concentration (which can either be inside or outside the cell). There is no energy (ATP) input and carrier proteins are not needed.
Oxygen molecules can diffuse into and out of cells
Facilitated diffusion is the same as above, but with the use of a carrier protein. Certain larger molecules are not able to diffuse directly into the cell and so need carrier proteins that form a channel through the phospholipid bilayer so the larger molecule can pass into/out of the cell. These larger molecules (carbohydrates etc.) have a unique carrier protein that will only allow passage to that molecule (yes this sentence doesn't make much sense
)
Glucose, amino acids can move into/out of cells through facilitated diffusion
Osmosis is the diffusion of water, and solutions with water as the solvent
Active transport makes use of carrier proteins, energy input and movement is often against the concentration gradient ( moving from an are of low to high
concentration). NOTE: I'm not sure whether this another type of diffusion
Nutrient ions can move into/out of cells via active transport (some may move through facilitated diffusion)
another note: I'm not intending to show off, I've got my bio half yearly in less than two weeks and wanted to regurgitate out what I know
The dot pts relating to osmosis and diffusion:
- Compare the processes of diffusion and osmosis
- Perform a 1st hand investigation to model the selectively permeable nature of a cell membrane (experiment)
- Perform a 1st hand investigation to demonstrate the difference between osmosis and diffusion (experiment)
Hope this helped