CELLULAR TRANSPORT

Cellular Transport

2 Kinds:

ACTIVE TRANSPORT
          - requires energy
Examples:
     Sodium-Potassium pump
     Bulk Transport

Bulk Transport

Endocytosis
     - engulfs
     - 3 kinds:

Phagocytosis
     - solid
Pinocytosis
     - liquid
Reverse Mediated Endocytosis
     - specific molecules

Exocytosis
     - reverse


PASSIVE TRANSPORT
          - does not requires energy
          - 2 kinds:

Diffusion
     - movement of molecules from an area of high concentration to an area of low concentration

Factors Affecting the Rate of Diffusion

1. Size of the diffusing molecule
2. Molecular weight of the diffusing substance
3. Structure and composition of cell
4. Concentration gradient
5. Temperature
6. Other external factors

Osmosis
     - the diffusion of water through a semipermeable membrane

hypotonic - the cell bursts
hypertonic - the cell shrinks
isotonic - nothing happens to the cell