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. Vocabulary
Solution- mixture in which one or more substances are UNIFORMLY distributed in another. “homogenous solution”
Solute- what gets dissolved.
Solvent- what does the dissolving.
Ex- salt water- salt is solute, water is solvent. Ice tea- mix=solute, water=solvent

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

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

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

9. 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!

10. 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)

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

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

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

14. Diffusion

15. Diffusion
Molecules moving from a greater concentration to a lower concentration
Ex: perfume
Simple diffusion: Oxygen, Carbon Dioxide, water and lipid soluble molecules

16. Vocabulary
Concentration gradient: difference in concentrations (amount of solute)
Equilibrium: particles/molecules are equal on both sides of membrane

17. More diffusion -> “equilibrium”!!

18. Osmosis

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

20. Iso – Hyper – Hypotonic Solutions

21. 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)

22. Plasmolysis

23. 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

24. Facilitated Diffusion

25. Facilitated Diffusion
Carrier Protein –
-protein recognizes substance->changes shape->delivers substance to inside of the cell
Facilitated Diffusion: water soluble molecules (hydrophillic). Ex: ions, amino acids (small proteins), and sugars

26. Ion Channels

27. 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

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

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

30. Active Transport

31. 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!

32. Endocytosis

33. 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

34. Exocytosis opposite of endocytosis!!