Cells: Diffusion & Osmosis

Diffusion
Passive Process --> Does not need a lot of energy to occur.

• Temperature
• The higher the temperature, the faster the rate of diffusion.
• The higher the temperature, the more kinetic energy the particles have. Thus, the particles can move from a region of higher concentration to a region of lower concentration.
• Particle Size
• The smaller the particle, the faster the rate of diffusion.
• Concentration Gradient
• The higher the difference between the concentration level of two regions, the higher the rate of diffusion.

Osmosis
Net movement of water molecules form a region of high water potential to a region of low water potential across a partially permeable membrane.

CONCENTRATION GRADIENT


Dehydrated animal cell - Crenated/Crenation
Hydrated animal cell - Burst/Lyse
Dehydrated plant cell - Cytoplasm shrinks away from the cell wall/Plasmolysis/Plasmolysed
Hydrated plant cell - Turgor/Turgid/Turgor Pressure


Describe

1. Establish which has higher water potential & lower water potential.
2. Water molecules moving in/out of the cell.
3. Impact on the cell.

Hypertonic - Having a higher osmotic pressure in a fluid relative to another fluid.

Hypotonic - Having a lesser osmotic pressure in a fluid compared to another fluid.

Isotonic - Having the same (or equal) osmotic pressure and same water potential.

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