5.1.2 and 5.1.3 Other Aspects of Membrane Structure and Membrane Fusion and Budding

Question 1

Glycosylation

Answer 1

Modified by conjugation with carbohydrates. Often used to traffic proteins to specific places in the cell or outside of cell (vesicles).

Question 2

Lipid Raft (composition + Usage)

Answer 2

Cholesterol and Sphingolipids. Important for cell signaling and tethering membrane proteins.

Question 3

Why Membrane Asymmetry?

Answer 3

Structural Integrity and Cell Signaling. The extracellular leaflet has a lot phospholipids that act as signaling pathways.

Question 4

What enzyme causes/maintains asymmetry?

Answer 4

Phospholipid translocases or Flippases. causes exchanges of lipids between membrane leaflets.

Question 5

Membrane Budding and Fusion

Answer 5

Causes changes in size, often caused by a hormone or neurotransmitter.
When two membranes come in close proximity, they begin to fuse lipids between leaflets forming a “Fusion Pore”