Osmosis

 Booklet 1: Osmosis and Plant Transport (Biology unit 2) 

What is osmosis? [3]

movement of water molecules from a high concentration of water to a low concentration of water [1] down the concentration gradient [1], through a semi permeable membrane [1].  

What is hyertonic and hypotonic?

Hypotonic- has a higher concentrationf water and a lower concentration of glucose solution

Hypertonic- has a lower concentartion of water and a higher concentartion of glucose solution.  

The glucose molecules are too large to pass through the mebrane. The water molecules will move, at random, throught the mebrane until the concentrations are equal on both sides of the membrane. The solutions are described as being ISOTONIC.       

2.1.3 Osmosis in plant cells (turgid, flaccid, plasmolysed)

when a plant cell is in placed in an isonic solution there is no net movement of water. 

when a plant cell is placed in hypotonic solution (high concentration of water) the water will move into the vacole and the cell membrane against the cell wall. This is called Turgid.

when a plant cell is placed in a hypertonic solution (low concntration of water) water will leave the vacuole and th cell membrane will no longer push against the cell wall. This is called Flaccid. 

If the cell continues to loose water, the cell membrane will pull away from the cell wall. This is called Plasmolysed. In his state the plant will wilt. 

Osmosis in plant cells

when animal cells are placed in isonic solutions (equal) there will be no net movement of water in or out of the cell (it will stay the same size)

when animal cells are placed in a hyertonic solution water will move out of the cell and will shrink (crenate)

when an animal cell is placed in a hypotonic solution (high concentration of water) water will move into the cell and it can …