1. Membrane Transport
Department of Biology, WCU

2. Introduction Environments Fluid movement Processes
Intra-, intercellular, extracellular - interstitial fluid
Fluid movement
Processes
passive
active

3. Diffusion 1. Simple Transport
movement from high to low concentration (e.g. food dye)
Transport
lipid soluble
lipid insoluble

4. Diffusion
2. Osmosis
diffusion through a semi-permeable membrane

5. Osmosis video

6. Diffusion
2. Osmosis
Osmolarity (mOsm)
Water tension called tonicity

7. Diffusion
Importance

8. Diffusion 3. Facilitated Requires a protein carrier (glucose)
Confirmational shape change

9. Active transport Requires carrier proteins
Against concentration gradient
Requires ATP
Types
symport
antiport (Na+K + ATPase pump)

10. Active transport
Na+/K+ pump

11. Bulk transport Large molecules Requires ATP (protein from Golgi) Types
exocytosis
endocytosis

12. Exocytosis e.g. hormones, mucus (goblet cells), wastes (dead cells)
Encapsulated in vesicle

13. Endocytosis
e.g. white blood cell engulf bacteria
Types
phagocytosis

14. Endocytosis
Types
Pinocytosis

15. Endocytosis
Types
receptor-mediated endocytosis (insulin)