Aim: How does Osmosis and Diffusion compare?

What is the diffusion of water called? Osmosis

OSMOSIS The movement of water from an area of high concentration to an area of less concentration.

What is meant by concentration? The amount of solute! Solvent: The liquid (ex. Water) Solute: The solid added to the liquid (ex. salt/sugar) Distilled water 100% pure water

*Solute + Solvent = Solution

Solution: A mixture of the dissolved material ( solute ) & the dissolving agent ( solvent ). Ex. sugar (solute) dissolved in water (solvent).

Concentration Differences: 1) A 90% salt solution vs. a 20% salt solution Which solution has more salt particles? The 90% salt solution Which solution has more water molecules? The 20% salt solution 2) A 60% salt solution vs. 80% salt solution? The 60% salt solution = more water The 80% salt solution = more salt

Which container has a greater concentration of water molecules? = Solute (salt) = Solvent (water) Which container has a greater concentration of solute molecules?

Selectively Permeable In which direction is osmosis going to occur? = Solute (sugar) = Solvent (water) Selectively Permeable

Why does this happen? OSMOSIS

Why are the water molecules diffusing to the left? Water molecules are red

The water is moving from an area of high to low!

Why does water go in and out of the cell? If solute is equal, then so is water amount SO molecules still move back and forth! To maintain DYNAMIC EQUILIBRIUM

What happens to an animal cell if it is surrounded by a low concentration of water? The Cell will shrink!! Salt sucks!!!!

What happens to an animal cell if it is surrounded by a high concentration of water? The Cell will swell or burst!

In which direction will osmosis happen? H2O

How is osmosis a form of passive transport? Osmosis is the movement of water from an area of high concentration to an area of low concentration. No ATP needed.

Practice Questions: 1. A cell containing 98% water in its cytoplasm is placed in a 20% salt solution. What will happen to the cell? The 90% salt solution 2. What will happen to a cell if it is placed into a concentrated salt solution? The cell will shrink ( salt sucks). 3. What will happen if a cell is placed in distilled water? The cell would burst, because inside the cell has a higher solute concentration than outside.