Zusammenfassung der Ressource
B3 - Osmosis
- Osmosis is the movement of water molecules across a partially permeable membrane
from a region of high water concentration to a region of low water concentration
- Partially permeable membrane- small holes in
it, only small molecules can pass throught it
- Water molecules pass both ways through the membrane.
This is because they move randomly all the time.
- So a strong sugar solution would become more dilute.
- Type of diffusion. Passive movement of water molecules.
- Water moves into and out of cells be osmosis.
- Tissue fluid surrounds the cells in the body. It will usually
have a different concentration to the fluid inside a cell so
water will move in and out by diffusion.
- If a cell is short of water, the solution inside will become
concentrated so the outside is more dilute so water will
move into the cell by osmosis. If a cell has lots of water,
the solution inside will be more dilute so watwer will be
drawn out of the cell and into the fluid by osmosis.