1. Syllabus update: Switch today (11/19) and tomorrow (11/20)
Do Now 11.19
OBJECTIVES:1. Identify three ways that active transport is different from passive transport Define endocytosis and exocytosis Describe the function of the sodium-potassium pump as an example of active transport.
TASK: 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.
TASK2:
Syllabus update: Switch today (11/19) and tomorrow (11/20)

2. Passive Transport Definition: Type 1 Type 3 Type 2 DIFFUSION OSMOSIS
The process of substances passing through the cell membrane WITHOUT ANY INPUT OF ENERGY BY THE CELL.
Passive Transport
Type 1
Type 3
Type 2
DIFFUSION
OSMOSIS
FACILITATED
DIFFUSION
Definition:
Solute molecules move from an area of high concentra-tion to an area of low conc. Powered by the random motion of molecules.
Key Term:
Equilibrium
Definition:
Cell uses carrier proteins in membrane to allow the diffusion of molecules that can’t pass through membrane alone.
Hypertonic:
Solute conc. Bigr
outside. H2O out
Definition:
Diffusion of water from an area of high H2O conc. (low solute conc.) to low (high solute conc.)
Required for
Ions
(charged
molecules)
Isotonic:
Solute conc. =
Inside & out.
No net H2O
change.
And
Hypotonic:
Solute conc. Lower outside.
H2O in. Hypo-Hippo
Large
Molecules

3. Active Transport
Active transport processes are different from passive ones:
Energy is required.
Substances move UP their concentration gradients from lower conc. to higher.
Equilibrium is PREVENTED.

4. 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

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

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

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

8. For Protists, Phagocytosis = Eating

9. 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)

10. Exocytosis

12. Endo and Exocytosis – quick review

13. 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!

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

15. Na+/K+ Pump… Drake demonstrates…

16. Recap: Active Transport Uses ATP
Active transport is different from passive in 3 key ways (energy, up gradient, no equilibrium)
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
moves 3 Na+ out and 2 K+ in per cycle.
Causes cells to be negatively charged.