1. BULK TRANSPORT IN CELLS
ENDO
Transport of many molecules into (“endo”) or out of (“exo”) the cell at once
EXO
Add arrows on your note blanks to indicate the direction of endocytosis and exocytosis relative to the cell membrane

2. ENDOCYTOSIS
Process by which cells take in molecules (such as proteins) or smaller cells by engulfing them.

3. Examples of endocytosis
White blood cells can engulf bacteria during infection
Single cell organisms like amoeba can engulf bacteria as food

4. Exocytosis
A cell directs the contents of secretory vesicles out of the cell membrane and into the extracellular space.

5. Exocytosis
proteins to be secreted to the extracellular environment, as well as membrane bound proteins and phospholipids that will become part of the cell membrane
A cell directs the contents of secretory vesicles out of the cell membrane and into the extracellular space.
The space outside of and between cells

6. Examples of exocytosis
Secretion of neurotransmitter proteins to send signal between neurons
exocytosis
exocytosis
receptor
Secretion of saliva from salivary glands in the mouth

7. Fluidity of the cell membrane makes endocytosis and exocytosis possible
Watch this animation to look for clues about why the cell membrane is considered “fluid”
time
Another AMAZING video to show real life membrane fluidity in action!

8. Why are membranes fluid? NOTE: fluid ≠ liquid
Phospholipids can move in the membrane because
there is weak to no bonding between phospholipid tails
kinks in the phospholipid tails prevent close packing
cholesterol keeps phospholipids from packing too close or drifting too far apart

9. 1.4.U2
“The fluidity of membranes allows materials to be taken into cells by endocytosis or released by exocytosis. Vesicles move materials within cells.”
Explain membrane fluidity
Define endocytosis and exocytosis
Explain how and where vesicles move within the cell