1. One curve represents the diffusion of glucose through the lipid bilayer, and the other represents the transport of glucose by facilitated diffusion. Which curve corresponds to facilitated diffusion? Explain your reasoning.
Do Now

2. Endocytosis “Endo-” means in. “cyto-” means cell.
“osis” means process of.
What does endocytosis mean?
Endocytosis: the process by which cells take in large amounts of material, by folding in the cell membrane

3. Endocytosis Example
Pinocytosis: non-specific endocytosis of small amounts of extracellular fluid.
Greek: “pino-” = “drinking”

4. Endocytosis Example Phagocytosis:
the endocytosis of solid particles such as bacteria, cell debris, or other solids
Greek: “phago-” = “eating”

5. Phagocytes
Phagocytes, such as some types of white blood cells, engulf foreign cells by phagocytosis.

6. For Protists, Phagocytosis = Eating

7. Exocytosis
Exocytosis is the same process as endocytosis, except in reverse.
The stuff leaving may be:
Proteins released into the ECF
New lipids for expanding the membrane
Membrane proteins
Chemicals for communication, etc. (e.g. dopamine)

8. Exocytosis

10. Endo and Exocytosis – quick review

11. The Sodium / Potassium Pump
The Na+/K+ pump is responsible for maintaining the electrical charge of a cell
Cells are negative
Communication, e.g. neurons
Cation uptake
It is an example of a membrane pump which move specific things into or out of the cell AGAINST THEIR CONCENTRATION GRADIENT.
Since it requires energy, it is an example of ACTIVE TRANSPORT!

12. How the Na+/K+ Pump Works
Don’t forget the animation….

13. Recap: Active Transport Uses ATP
Endocytosis = cell taking in material by infolding the membrane.
Pinocytosis = “cell drinking” ECF
Phagocytosis = “cell eating” bacteria, etc.
Exocytosis = cell exporting materials in bulk.
Na+/K+ Pump = an example of a membrane pump that moves sodium ions out and potassium ions in AGAINST the concentration gradient. Causes cells to be negatively charged.