1. Chapter 2 section 2.2 Pages 81-86
Membranes
Chapter 2 section 2.2
Pages 81-86

2. Membranes
In a cell, what is the purpose of a membrane?

3. Fluid mosaic model
Most membranes are made up of a combination of lipids, proteins and carbohydrates
Membranes aren’t rigid but instead the parts are free to move around
Semi-permeable

4. Lipids in the membrane Dominant lipid is the phospholipid
Chemical properties of
head?
tail?

5. Fluidity of membrane How fluid a membrane is depends on: Temperature
Composition (types) of lipids
Temperature:
What happens at high temperatures?
Low temperatures?

6. Fluidity of membrane How fluid a membrane is depends on: Temperature
Composition (types) of lipids
Composition:
Saturated vs unsaturated
What does each of these types of lipids do to the membrane?

7. Fluidity of membrane How fluid a membrane is depends on: Temperature
Composition (types) of lipids
Composition:
Cholesterol?
What does it have to do with anything?

8. Membrane proteins Roles: Transport
Moving substances across the membrane
Specificity?
Examples?

9. Membrane proteins
Roles:
Enzymes
Catalyze reactions
Examples?

10. Membrane proteins Roles: Attachment and recognition
Some act as points of attachment
i.e. a cell’s cytoskeleton is anchored to membrane and gives shape and rigidity
Recognition
Allows certain components to recognize certain cells
WBC recognize a cell as “self” based on membrane proteins present

11. Membrane proteins Roles: Signaling
Are recognized and bound by certain chemicals like hormones
Pass this “signal” into the cell, setting of a cascade of events

12. Membrane proteins
Types:

13. Membrane proteins Types: Integral membrane proteins
Where are they found?
Are they hydrophobic, hydrophilic or both?
What does transmembrane mean?
Examples?

14. Membrane proteins Types: Peripheral membrane proteins
Where are they found?
Are they hydrophobic, hydrophilic or both?
Examples?

15. Membrane carbohydrates
Glycolipids:
Glycoproteins:
Roles: