Tonicity

REVIEW of Passive Transport Osmosis is the movement of water into and out of the cell membrane. It is a SPECIAL KIND of Diffusion. Water will move from an area of HIGH water concentration to an area of LOW water concentration on its own with NO ENERGY! The 3 types of Osmosis are known as the types of TONICITY.

Tonicity Describes the ability of a solution to cause a cell to gain or lose water. It depends on the concentration of a solute.

Solutions Remember that a solute is dissolved into a solvent to make a solution. Solute + Solvent  Solution

Types of Solutions There are 3 types of solutions. This is based on a comparison of the concentration of solute (the part being dissolved) in each. Imagine placing a cell into a solution and comparing the concentrations of solute in both. Solution Cell

In each of the following solutions, osmosis takes place In each of the following solutions, osmosis takes place. Remember this rule: WATER FOLLOWS SOLUTE = SOLUTE SUCKS

Remember: Solute Sucks draw and label the pics in your IAN

Types of Solutions 1) Isotonic Solution – The concentration of solute outside is equal to the concentration inside the cell. Water is moving = into and outside of the cell, EQUALLY! Draw and label the pics. Normal in animal cells Solution Cell Flaccid (not firm) in plants

Types of Solutions 2) Hypotonic Solution – HIGH concentration of solute inside the cell, LOW concentration of solute outside the cell . Water will follow the solute and move into the cell to try and create a balance, equilibrium, homeostasis. The cell will swell up. An animal cell will undergo cytolysis=lysed=burst (draw, label pics) A plant cell has a cell wall so it will not burst, but will be come very TURGID, they swell and are firm, Normal for plants. Cell

Types of Solutions 3) Hypertonic Solution – LOW concentration of solute in the cell and HIGH concentration of solute outside the cell. Water will move out of the cell to try and balance the concentrations so the cell will shrivel. An animal cell will undergo crenation (shriveling) (draw, label pics) A plant cell has a cell wall that remains the same but the cytoplasm will shrivel inside the cell membrane, which is called plasmolysis (plasmolyzed). Cell

What are the parts of a solution? Solute and Solvent

Which way does water move in an isotonic solution? IN and OUT of the cell because it is BALANCED

Which way will water move during osmosis? What is the rule? Water moves TOWARDS Solute. SOLUTE SUCKS!

Inside the cell; Water will go INTO the cell. In a hypotonic solution, where is the higher concentration of solute? (inside or outside of the cell?) Which way will water move? Inside the cell; Water will go INTO the cell.

Outside the cell; Water will go OUT of the cell. In a hypertonic solution, where is the higher concentration of solute? Which way will water move? Outside the cell; Water will go OUT of the cell.

Types of Solutions flaccid

HOMEWORK Do the Osmosis Worksheet for Homework. It is due at the BEGINNING of class tomorrow, 3-22-16!