Both eggs sat in vinegar solution over the weekend and then placed in two different solutions: freshwater and high solute solution (corn syrup). Egg 1 (the egg on the left) was placed in freshwater. Notice that after being in freshwater for 24 hours, it gained 5.6 g of mass. This is an example of the effects of a hypotonic solution where water is initially at a higher concentration outside the cell and enters the cell to reach equilibrium. Egg 2 (the egg on the right) was placed in a high solute solution (corn syrup). Notice that after being in high solute solution for 24 hours, it lost 34.09 g of mass! This is an example of the effects of a hypertonic solution where water is initially at a higher concentration inside the cell and leaves the cell to reach equilibrium.
Diffusion describes the tendency of materials (solutes in particular) to want to move from areas of high concentration to areas of low concentration.
The cell membrane is made of two layers of lipids. On each lipid molecule, there is a part of the molecule that repels water (hydrophobic) and a part that does not repel water (hydrophilic). The only way the lipid molecules could arrange themselves along the border between the inside of the cell (where there is water) and the outside of the cell (where there is also water) is to line up in two layers, back-to-back. The hydrophilic sides of molecules face the water in or out of the cell, while the hydrophobic portions are protected within.
In this activity, candy corn modeled the lipid molecules where the yellow part is hydrophilic and the orange/white portion is hydrophobic. Unit 3: Life, Cells, & Energy The role of the cell membrane is to regulate (control) what enters and leaves the cell, allowing some materials in/out while preventing other materials from doing so. In a similar way, a screen window allows certain things to enter/leave the home, yet prevents others from doing so. The cell membrane prevents certain materials from entering the home or leaving the cell, just like a screen window prevents certain things from entering the home or leaving the home. A cell membrane allows some materials to either move into the cell or out of the cell, much like a screen window which allows some things into a home or out of the home.
For starters, here is the study guide: Here is a screen-shot of the in-class review: Here are the online lessons:
Don't forget your notes:
Here are copies of notes provided by your peers:
Here are previous blog entries: Play the Kahoot! HERE Unit 3: Life, Cells, & Energy For starters, here is the study guide: Here is a screen-shot of the in-class review: Here are the online lessons:
Don't forget your notes: Here are copies of notes provided by your peers:
Here are previous blog entries:
Play the Kahoot! HERE Unit 3: Life, Cells, & Energy |
Current Unit (Biology)Prepare for your next assessment...SchoologyMCAS CountdownMr. Dubuque's
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