1. Transport in plants
Grade 8 biology

2. Diffusion
A type of passive transport(not requiring energy) involving the movement of particles from an area of higher concentration to an area of lower concentration.
Diffusion is spontaneous and automatic.

3. Osmosis
passage of water from a region of high water concentration, through a semi-permeable membrane, to a region of low water concentration.

4. Endosmosis inward osmosis
inward passage of liquid through a membrane of a cell or cavity

5. Exosmosis outward osmosis
outward passage of liquid through a membrane of a cell or cavity

6. Plasmolysis

7. Hypertonic hypotonic and isotonic solutions
Videos on
Elodea in hypertonic solution
Elodea in hypotonic solution
Demonstration

8. Turgor pressure( video)
also called turgidity,
is the main pressure of the cell contents against the cell wall in plant cells.
Turgor is a force exerted outward on a plant cell wall by the water contained in the cell.
This force gives the plant rigidity, and may help to keep it erect.
Turgor can result in the bursting of a cell.

9. Exercise
Write a letter from the cell membrane to cell wall of a plant cell, explaining how their closeness or interactions depend on the availability of water in their respective surroundings.
Make sure you use all the terms you have learnt till now !!

10. Wall pressure
It is the pressure exerted by the cell wall on the contents of the cell, including the cell membrane.

11. Turgid and flaccid cells
Plant cells need to be turgid (i.e rigid) to support plant tissues.
Plant cells become turgid when water moves into the cell by osmosis, and the central vacuole swells and pushes against the cell wall.
When plant cells are placed in concentrated sugar solutions they lose water by osmosis and they become "flaccid"; this is the exact opposite of "turgid"
Turgid plant cells contain more water than flaccid cells and exert a greater osmotic pressure on its cell walls.