Lipids

Question 0

What is the technique used to identify new, minor lipids?

Answer 0

mass spec. separates by structure

Question 1

What are the roles of lipids in the cells?

Answer 1

1. Energy Storage
2. Cell communication
3. Cell/ membrane structure
4. Regulation of various biological processes

Question 2

Eicosanoids

Answer 2

produced by macrophages; 2nd messengers, role in inflammatory diseases, derivative of arachidonic acid (stimulus stimulates phospholipase A2s, that increase concentration of eicosanoid precursers)

Question 3

Hydrophobic effects

Answer 3

Driven by entropic effect of water organization around fat droplets; sizable energy involved (25 cal/A2)

Question 4

Critical micelle concentration

Answer 4

concentration at which micelles form; monomer saturation so as concentration of monomers increases above cmc you get all micelle as a constant amt of monomers as all monomers are formed into micelles

Question 5

Type II alveolar epithelial cells

Answer 5

produce surfactant (a phospholipid that decreases surface tension) and helps us breathe

Question 6

Role of cholesterol in fluidity of bilayer

Answer 6

keeps bilayer in intermediate fluidity (increases when cold, decreases when hot)

Question 7

What is the role of scramblase in forming blood clots?

Answer 7

In platlet cells, calcium activates scramblase which allows flip flopping in both directions across the bilayer, induces clotting