Diffusion Flashcards
Diffusion
The spreading out of the particle of a gas or of any substance in a solution (a solute). This results in the net movement of particles from an area of high concentration to an area of lower concentration
What happens when there is a big difference in concentration between 2 areas?
Diffusion will take place quickly. Many particles will move randomly towards the area of low concentration. Only a few will move randomly in the other direction.
What happens if there is only a small difference in concentration between 2 areas?
Diffusion will be quite slow. The number of particles moving into the area of lower concentration by random movement will only be slightly more than the number of particles that are leaving the area.
Concentration gradient
The difference between 2 areas of concentration
How does temperature affect the rate of diffusion?
An increase in temperature means that the particles move around more quickly so diffusion takes place more rapidly as the random movement of the particles speed up.
Partially permeable membranes
Membranes that only let some types of particles through
Osmosis
When water moves across a partially permeable membrane from an area of high concentration to an area of lower concentration
Hypotonic
When the concentration of solutes in the solution outside the cell is lower than the concentration inside the cell
Isotonic
When the concentration of solutes in the solution outside the cell is the same as the concentration inside the cell
Hypertonic
When the concentration of solutes in the solution outside the cell in higher than the concentration inside the cell
Turgor pressure
When the pressure inside the plant cell builds up until no more water can physically enter the cell
Plasmolysis
When more water is lost by osmosis, the vacuole and cytoplasm shrink so eventually the cell membrane pulls away from the cell
