Solutions Solute – The substance that dissolves to form a solution eg salt Solvent – The...
-
Upload
merry-parker -
Category
Documents
-
view
231 -
download
0
Transcript of Solutions Solute – The substance that dissolves to form a solution eg salt Solvent – The...
SolutionsSolute – The substance that dissolves to form a solution eg saltSolvent – The substance in which a solute dissolves eg waterSolution – A mixture of one or more solutes dissolved in a solvent eg sea water
Solute
Solvent
DIFFUSION & OSMOSIS
DIFFUSION• Diffusion animation
Diffusion is the net movement of particles from a region of higher concentration to a region of relatively lower
concentration. No input of energy is required.
DIFFUSION & OSMOSISOSMOSIS• Osmosis animation
Osmosis is the net movement of a solvent, usually water, across a
differentially permeable membrane. The net movement of water occurs
from the side of the membrane where there is a weak solution (high
water concentration, low solute concentration) to the side of the
membrane where there is a strong solution(low water concentration,
high solute concentration).Osmosis does not require energy
input.
Osmosis
Amoeba are small unicellular organismswith a large SA:V
Amoeba in action 1Amoeba in action 2
Some substances can diffuse into /out of these cells very efficiently as a result of the large SA: V ratioLarger food particles can be engulfed: phagoctosis
Plasma Membranes
Functions of the cell membrane include:1. It gives a definite shape to the cell.2. It contains and provides protection to the internal contents of the cell.3. It is selectively permeable.4. It can take in solid and liquid materials by in folding.5. In animal cells, it is involved in the formation of vesicles, cilia, flagella, microvilli, etc. Plasma Membrane overview 5 min
Openings both sides eg channels for ion transfer
Binds hormones and other substances
Attach to carbohydrates act as antigens
Link cells together
Fluid Mosaic model of plasma membranes
Web page including good animation
Cell-Membrane-Function
Plasmolysis
Hemolysis & Crenation
Passive v Facillitated Diffusion