1. Biochemistry
Membranes

2. Biochemistry – Membranes

3. General Properties Fluid Mosaic Phospholipid bilayer
GLYCEROL
Fluid Mosaic
Phospholipid bilayer
Selectively Permeable
Asymmetric
Outer and inner leaflet
Lipid + protein + cholesterol + CHO
Amphipathic(hydrophillic and hydrophobic)
NO 
Yes
NAM SM PC
Sphingosine L V
Choline

4. Lipid + Protein + Cholesterol
Lipids
Phospholipids, NOT TAGs
Lecithins such as Phosphatidylcholine (outer leaf)
Sphingomyelin (outer leaf, has choline!)
Gangliosides (lipid with sugar)
N-acetylneuraminic acid
Proteins
Peripheral = on periphery
Integral = goes all the way through membrane
Leucine and valine are found on interior of globular proteins(nonpolar, hydrophobic aa)
Cholesterol
Most abundant non-phospholipid component of membrane
CHO
Attached to lipids(gangliosides) and proteins GS SM
NAM
Sphingosine L V
Choline

5. Types of movement Passive Diffusion(uses no energy, -ΔG)
Simple diffusion (if water, osmosis)
Facilitated diffusion (mediated diffusion)
Swimming downstream
Active transport (uses energy +ΔG)
Primary active transport
Secondary active transport
Swimming upstream
NOTE: delta G = gibbs free energy
-ΔG = spontaneous
+ΔG = not spontaneous

6. Selectively permeable
No = large and charged
Need protein transport systems to move across
Yes = small, nonpolar, uncharged
Steroids, crol is nonpolar

7. Types of movement 1. Simple diffusion (if water, osmosis)
Facilitated diffusion (mediated diffusion)
Primary active transport
Secondary active transport
Simple Diffusion
Facilitated Diffusion
Active Transport
No nrg
With gradient
Protein transporter

8. Simple Diffusion No energy Movement from high to low concentration
Down gradient
Aka With the gradient
Swimming downstream
Penetrating solutes
Go through with no help

9. Facilitated Diffusion
No energy used
Down gradient
Non-penetrating solutes
Need help
Uses proteins
Saturation kinetics of binding sites
[High solute], all binding sites used up
(enzyme lecture)

10. Simple diffusion vs facilitated diffusion
Energy used
Protein transporter
Solutes
Saturation kinetics
Simple Diffusion
No, down gradient no
penetrating
Facilitated diffusion
yes
Non-penetrating

11. Simple Vs Facilitated Diffusion
How is simple diffusion different than facilitated diffusion?
Facilitated involves saturation kinetics
How is facilitated diffusion different than active transport?
Facilitated diffusion requires a concentration gradient.
Active transport doesn't’t, can just use ATP
What is similar between facilitated diffusion and active transport
Saturation kinetics and competitive inhibition

12. Primary Active Tport Sodium potassium ATP pump(NaKA) Against gradient
Up gradient
Directly uses ATP
Gain in free energy

13. Secondary Active Tport
Indirectly uses ATP
Aka cotransport aka countertransport
Against the gradient
Binding kinetics
Gain in free energy

14. +ΔG Passive Transport Active Transport -ΔG Simple Diffusion
Facilitated
Diffusion
Primary AT
Secondary AT
Osmosis
Channel Proteins
Carrier Proteins
AKA
Cotransport