Movement through cell membranes

Diffusion

It is the passive movement of particles from an area of high concentration to an area of low concentration

Factors affecting diffusion

Concentration gradient, temperature and surface area between membranes

Active transport

It is the movement of a substance from an area of low concentration to an area of high concentration across a semi-permeable membrane using energy

Where does active transport occur

In root hairs to absorb minerals

Osmosis

It is the passive movement of water from an area of high water concentration to an area of low water concentration across a selectively permeable membrane

Where does osmosis occur

In plant to take in water

Isotonic

The external solute concentration is equal to the internal solute concentration

Hypertonic

The external solute concentration is greater than the internal solute concentration

Hypotonic

The external solute concentration is less than the internal solute concentration

Osmoregulation

It is the means by which cells keep the concentration of cell cytoplasm or blood at a suitable concentration

Hypotonic solution in animal cells

The cell will swell and burst

Hypertonic solution in animal cells

The cell will shrink and shrivel

Hypotonic solution in plant cells

The cell will swell and become turgid

Hypertonic solution in plant cells

The cell shrivels and becomes plasmolysed

Turgor pressure

It is the pressure of the cells contents and cell membrane on the cell wall

Plasmolysis

It is the loss of water from a plant

Flaccid plant cell

It is one in which the cell membrane is not pressed tightly against the cell wall