Answer at the top of your guided notes for today Can you drink too much water? Can you drink so much water that it kills you? Explain your answer.

Yes! SACRAMENTO, Calif.  Jennifer Strange, 28, was found dead in her home due to water intoxication hours after taking part in the “Hold Your Wee for a Wii” radio contest which promised a Nintendo Wii video game system for the winner.

How do our bodies maintain that balance? Drinking too much water is called water intoxication, or hyponatremia, which means that your blood is too diluted and does not contain enough salt. Without the right balance of salt and water, your brain cells swell and burst, leading to death. How do our bodies maintain that balance?

Cellular Transport Part 1

How does cellular transport help us stay alive? Essential question How does cellular transport help us stay alive?

objectives By the end of this lesson I will be able to: Understand how cellular transport contributes to homeostasis Identify solute, solvent, and solution Describe concentration Predict what will happen to a cell in an isotonic solution, a hypertonic solution, and a hypotonic solution Differentiate between passive and active transport

Dynamic equilibrium Continuous movement but no overall change Think: I have 25 students in my class. Two leave, then three enter, then one more leaves. How many students am I left with? The balance is maintained

Take out a sheet of paper. Put your name on it Take out a sheet of paper. Put your name on it. Using complete sentences, write step by step how you make Kool-Aid. Must be completed silently! You have 5 minutes. When finished, come get a cup.

solutions Solvent – the larger material {liquid} that dissolves the solute Water is considered the “universal” solvent Solute – smaller substance that is dissolved by the solvent. Ex. salt & sugar Solution – Complete mixture of solute and solvent Ex. Sweet tea

Concentration Definition: The amount of solute in a given solution For example, the more people in a classroom, the higher the concentration. People=“solute” Room=“solution” Write your own example. Describe the meaning of concentration to a non-biology student.

Concentration review In one cup, you put half a packet of Kool-Aid powder. In the next cup, you put the whole packet in. Which cup contains the more concentrated solution?

Quick Check! Go back to your Kool-Aid recipe. Rewrite it correctly including the following vocabulary words: solute, solvent, solution, concentration, and dynamic equilibrium

Water moves from a high concentration to a low concentration Why did that woman’s brain cells swell? **Write your thoughts down on your notes

Osmosis Osmosis is the process of water moving from high to low concentration across a membrane.

The three types of solutions The three types of solutions **The name describes the amount of solute outside of the cell

isotonic When a cell is in a solution that has the same concentration of water and solutes Solution has achieved dynamic equilibrium All solutions make changes to be isotonic

hypertonic A cell is in a solution that has a higher concentration of solute outside of the cell Hyper means higher {more concentrated} Think: more salt outside the cell, therefore less water outside the cell Where will the water move?

hypotonic A cell is in a solution that has a lower concentration of solute outside of the cell Hypo means lower {less concentrated} Think: less salt outside the cell, therefore more water outside the cell Where will the water move?

predict You put red blood cells into the following solutions: Isotonic Hypotonic Hypertonic Predict what will happen in each of the solutions. Think: Where will the water move?

answers In an isotonic solution, the cell will stay the same size In a hypertonic solution, there is more solute (and therefore less water) outside the cell. Water will move outside the cell and therefore shrink. In a hypotonic solution, there is less solute (and therefore more water) outside the cell. Water will move inside the cell and therefore swell.

Back to the essential question How does cellular transport help us stay alive? Things “naturally” move from a high concentration to a low concentration. Why?

Passive Transport Movement of materials in & out of the cell without {NO} Energy Hypertonic High Low Concentration Concentration (hypertonic) (hypotonic) Hypotonic

Movement of materials in & out cell WITH energy Active Transport Movement of materials in & out cell WITH energy High Low Low

Gummi bear mini-lab Take out your gummi bear predictions HW: rewrite what actually happened using the following: osmosis, hypotonic, hypertonic, isotonic, and concentration. Be sure to say if osmosis is an example of passive or active transport.