1. Transport-cell membrane
Do Now:
What is homeostasis?
What is transport?
Brainstorm:
Can you brainstorm one way that transport helps to maintain homeostasis in your body? (explain)

2. Definitions….. TRANSPORT
-absorption, distribution, circulation, cyclosis, osmosis, diffusion
HOMEOSTASIS
-maintaining a stable internal environment

3. What does venom have to do with cell membranes?
Brown Recluse Spider Bite!

4. Western Diamondback Rattlesnake bite!

5. Why is the cell membrane so important???

6. Selectively permeable membrane Semi permeable membrane
Names!
Cell membrane
Plasma membrane
Selectively permeable membrane
Semi permeable membrane

7. Honors Know diagram on pg 82!
Variety of Proteins:
I. Glycoproteins
Receptor protein
Recognition proteins
Enzymatic proteins
Attachment proteins
Transport proteins

8. Functions of the Cell Membrane
Protects the cell
Regulates what goes in and out of cell
Helps to communicate with other cells
Creates attachments between cells
Dynamic!

9. Fluid Mosaic Model dev. By Singer & Nicolson 1972
Proteins move within layers of lipids w/I viscous fluid
Hydrogen bonds can form between water and phospholipid heads inside and outside of cell
The more double bonds there are in the tails the more fluid the membrane
Incr. in temp. causes membr. To be more fluid (because mol. Move faster)
Decr. Temp. (mol. Move slower -> less fluid)

10. Active & Passive Transport Illustrations
Chapter 5 Lab Biology
Chapter 5 Honors Biology

11. Movement from a high concentration to a low concentration!
Passive Transport
Requires NO energy!!
Movement from a high concentration to a low concentration!

12. Passive Transport 1. diffusion 2. osmosis 3. facilitated diffusion
4. diffusion through ion channels

13. Diffusion

14. Diffusion
Molecules moving from a greater concentration to a lower concentration
Ex: perfume

15. Vocabulary Concentration gradient: difference in concentrations
Equilibrium: particles/molecules are equal on both sides of membrane

16. More diffusion -> “equilibrium”!!

17. Osmosis

18. Osmosis
Movement of WATER from a high concentration to a low concentration across the cell membrane

19. Iso – Hyper – Hypotonic Solutions

20. Vocabulary
Isotonic: concentration inside and outside of cell are the same  no diffusion
Hypertonic: when concentration of solute outside of cell is greater, water moves out of cell (shrink)
Hypotonic: concentration of solute inside of cell is greater, water moves into cell (burst)

21. Plasmolysis

22. Plants!
Plasmolysis = cell shrinks away from cell wall due to water loss ex: drought (low rain fall) causing plants to wilt
Turgor Pressure = cell wall sustains shape, otherwise would explode

23. Facilitated Diffusion

24. Facilitated Diffusion
Carrier Protein – helps mol. Across membrane that are hydrophobic or too large
-protein recognizes substance->changes shape->delivers substance to inside of the cell

25. Ion Channels

26. Ion channels -allows ions Ca2+ and Cl- to enter cell
Some are open all the time
Others are gated and will open when
Cell membrane stretches
Electrical signals
Chemical signals

27. Movement from a LOW concentration to a HIGH concentation!
Active Transport
REQUIRES ENERGY!
Movement from a LOW concentration to a HIGH concentation!

28. Active Transport
1. Sodium Potassium Pump
2. Endocytosis
3. Exocytosis

29. Active Transport

30. Sodium Potassium Pump -pumps like to keep ions in balance
3 Na+ out for every 2 K+ in
This creates a build up of Na+ outside cell and K+ inside cell forming a net electrical charge across the membrane
Allows for nerve impulses
Contraction of muscles
1/3 of all energy in animal cells goes to running this pump even as we sleep!

31. Endocytosis

32. Endocytosis
Take in external fluid, macromolecules and other large particles.
Forms “vesicle” some fuse with lysosomes (digestion) others fuse with membrane of other organelles.
2 Types: a) pinocytosis – cell drinking fluid
b) phagocytosis – cell eats

33. Exocytosis opposite of endocytosis!!