Osmosis Flashcards
What is osmosis?
Osmosis is the movement of water molecules from a place where they are in high concentration to a place where they are in a low concentration, through a partially permeable membrane.
Dilute solutions
A solution where there is a high concentration of water molecules.
Concentrated solutions
A solution where there is a low concentration of water molecules.
Same concentration of water molecules
When there is the same amount of water molecules on either side of the partially permeable membrane, the movement of water molecules will be the same in both directions.
In cells
Water moves into and out of cells via osmosis.
In plants
Plants take up water through their roots via osmosis.
Osmosis in cells
Osmosis in cells is the net movement of water molecules from a dilute solution to a more concentrated solutions through a partially permeable cell membrane.
Hypertonic solutions
Higher concentration of water molecules on the inside of the cell so the water will go out of the cell.
Hypotonic solutions
Higher concentration of water molecules outside of the cell so water will go into the cell.
Isotonic solutions
The same amount of water molecules on the inside of the cell as on the outside.
Lysis (Red blood cell)
Is when the cell is bursting, this happens in Hypotonic solutions.
Crenation (Red blood cell)
This is when the cell is shrinking because the water is leaving the cell, this happens in hypertonic solutions.
Normal (Red blood cell)
The cell is in its normal state and this happens in isotonic solutions.
Turgid (plants)
This is when there is too much water on the inside of the cell so the water is pushing against the cell wall making it stiff and turgid, this happens in a hypotonic solutions as the water is going into the cell.
Plasmolysis (plants)
This is when a plant cell has too little water in the cell so it will shrivel up and become weak.
Flaccid (plants)
This happens when there is enough water in the cell that it doesn’t shrink and doesn’t become turgid. This happens ion an isotonic solution.
Temperature
The higher the temperature the more kinetic energy it has, therefore increasing the rate. And vise versa.
Surface area
The larger the surface are the quicker it will happen.
Distance
The shorter the distance the molecules have to travel the quicker it will be.
Concentration gradient
The bigger the difference in concentration the faster the rate.
Visking Tube
Visking tubing is made from a plastic that has small pores (holes) in it. The pores are larger enough for water molecules to go through it but not sugar molecules like sucrose. Therefore we call it a partially permeable membrane and osmosis can happen across it.
