1. 7-3 Cell Membrane
The cell membrane regulates what enters and leaves the cell
It is made of a double layer sheet called a lipid bilayer

2. Proteins move material across the cell membrane
Carbohydrates act like chemical identification cards
Outside
of cell
Inside
(cytoplasm)
Cell
membrane
Proteins
Protein
channel
Lipid bilayer
Carbohydrate
chains

3. Cell Walls They are found in plants, algae, fungi and prokaryotes
They are OUTSIDE of the cell membrane
It provides support and protection for the cell
They are made of cellulose

4. Diffusion The cytoplasm is a “solution” of many substances in water
Concentration=mass/volume
Diffusion is the process by which molecules move from an area of high concentration to an area of low concentration

5. Glucose
molecules
High
Concentration
Cell
Membrane
Low
Concentration
Protein
channel

6. Osmosis
Selectively permeable means that only some substances can pass through
Osmosis is the diffusion of water through a selectively permeable membrane

7. Water diffuses from an area of high concentration to an area of low concentration
Diffusion will stop once equilibrium is reached

8. In comparing the inside of the cell to the solutions on the outside of the cell:
Isotonic- the solution on the outside has the same concentration as the solution inside the cell
Hypertonic- the solution outside has a HIGHER concentration of solutes than the solution inside the cell.
Hypotonic- the solution outside has a LOWER concentration of solutes than the solution inside the cell.
Pressure is exerted on the hypertonic side

11. Facilitated Transport
Also known as Facilitated Diffusion
Molecules that cannot pass through the lipid bilayer move through protein channels instead
Protein channels allow large molecules to pass

12. Active Transport
The energy-requiring process that moves material across a cell membrane against a concentration difference
Active transport does not always require transport proteins

15. Endocytosis- process of taking materials into the cell by means of infoldings of the cell membrane (forming a vacuole in the cytoplasm)
Phagocytosis- process of taking large particles into the cell
Exocytosis- the release of large amounts of material from the cell