1. Molecule Movement & Cells
Passive Transport
Active Transport

2. Solution Differences & Cells
solvent + solute = solution
Hypotonic
Solutes in cell more than outside
Outside solvent will flow into cell
Isotonic
Solutes equal inside & out of cell
Hypertonic
Solutes greater outside cell
Fluid will flow out of cell

3. Passive Transport No energy required Move due to gradient
differences in concentration, pressure, charge
Move to equalize gradient
High moves toward low

4. Types of Passive Transport
1. Diffusion
2. Osmosis
3. Facilitated diffusion

5. Carrier Proteins
Cells have proteins embedded in the cell membrane to help large molecules get through.
These proteins are celled carrier proteins.

6. Process of Facilitated Transport
Protein binds with molecule
Shape of protein changes
Molecule moves across membrane

7. Facilitated Diffusion with CARRIER PROTEINS
Animation from:
Carrier protein
grabs molecule,
changes shape, and
flips across to
other side like a
revolving door

8. Ion CHANNELS ION CHANNELS charged
Membrane proteins
create a tunnel through which Ions
can pass.
ION CHANNELS
charged
_______________ allow________ ions to get past the ____________ lipid center
hydrophobic

9. What if cell needs to move a molecule _________ the CONCENTRATION GRADIENT? _______________
AGAINST
(LOWER  HIGHER)
Cell example:
Want to put MORE glucose
into mitochondria when there is
already glucose in there
Image from:

10. Active Transport Molecular movement Requires energy (against gradient)
Two types
pump
Endo or Exocytose

11. Pumps
Carrier proteins that change shape for molecules that are not the correct shape.
Completely changing shape requires energy.

12. PUMPS ___________ transport (requires energy from ______)
Can move molecules from _____ concentration
to ______
Example: nerve cells Na+ is pumped out of cells at same time K + is taken into cells
ACTIVE
ATP
low
high

13. Endocytosis Movement of large material Movement is into cells
Particles
Organisms
Large molecules
Movement is into cells
Types of endocytosis
bulk-phase (nonspecific)
receptor-mediated (specific)

14. Process of Endocytosis
Plasma membrane surrounds material
Edges of membrane meet
Membranes fuse to form vesicle

15. Forms of Endocytosis Phagocytosis – cell eating
Pinocytosis – cell drinking

16. Exocytosis
Reverse of endocytosis
Cell discharges material

17. Exocytosis Vesicle moves to cell surface Membrane of vesicle fuses
Materials expelled

18. WHITE BLOOD CELL ENGULFING BACTERIA (Phagocytosis)

19. INSULIN being released by pancreas cells using exocytosis

20. INSULIN being released by pancreas cells using exocytosis