Bellwork - Have slate, marker & eraser on desk

Bellwork- Have slate, marker & eraser on desk

1. Draw a BEFORE picture of YOUR egg in the beaker and label where you think these 4 things were at the BEGINNING of the experiment: sugar/salt, water, cell membrane and cell

2. Draw an AFTER picture of YOUR egg in the beaker and label where you think these 4 things were at the END of the experiment: the sugar/salt, water, cell membrane, and cell

3. When finished complete your textbook notes for 3.5 (sections: inside & outside, diffusion, osmosis) OR review the textbook notes if already finished TIME IS UP @ 1:48

Textbook TimeSet up paper for

textbook notes on these sections of 3.5 today:

• Inside & Outside• Diffusion• Osmosis

3.5 Cells and Their Environment Textbook Notes

Vocabulary:1.

2.

3.

4.

5.

6. (not today)

7. (not today)

Inside and Outside-Be prepared to stop:(sentence summaries- 1 sentence summary for each paragraph)

Finished early? Begin graphing solute/ conc vs change in weight for egg lab

IV=X-axis, DV=y-axis

What would be different about skateboarding UP this hill rather than DOWN it?

Cell Membrane & Transport Notes

Passive Transport• Passive transport – Solute passes through membrane– NO energy required (like skateboarding DOWN a hill)– Only SMALL, uncharged molecules

Do you see WHERE in the membrane the

small molecules would slip through?

Active Transport• Active Transport– Solute passes through membrane– ATP energy required (like going UP a hill)– Moves large & charged molecules

Do you see WHERE in the membrane the

large/charged molecules would get

moved through?

Which kind of transport happened during the egg lab? Use the definitions to explain WHY.

Passive Transport• Passive transport – A solute passes through the cell membrane– NO energy required (like skateboarding DOWN a hill)– Only SMALL, uncharged molecules can do this

(salt breaks apart into Na+ and Cl- ions, and sugar is

a large macromolecule)

If the salt and sugar could not pass the membrane…WHAT DID MOVE? How did the eggs change weight?

Osmosis!!!• Movement of water

across a semi-permeable membrane:

Water moves from LOWHIGH concentration areas

Memory strategy: “Water follows the salt”

0% salt

25% sugar

What does osmosis tell us about the salt & sugar concentrations INSIDE of the egg if “water follows

the salt”?

50% salt

Does this make sense? Think about what an egg is…

Names for concentrations:

Isotonic• Iso= same• Same concentration outside the cell as inside

Hypertonic• Hyper= more/too much• Higher concentration solution outside the cell

Hypotonic• Hypo= less/too little• Lower concentration solution outside the cell

Closure

• Use osmosis to explain why your fingers get wrinkly when you’re in a pool for too long.