Lipids 2

Question 1

Excess acetyl-CoA is exported from teh mitochondria through what pathway?

Answer 1

citrate cleavage pathway

Question 2

What enzyme is used to convert malate to pyruvate?

Answer 2

malic enzyme

Question 3

High citrate concentrations indicates that the CAC is not acble to process all of the acetyl COA from the break dow of carbs meaning what?

Answer 3

glycolysis slows down and FA synthesis ramps up

Question 4

What is the committed/main regulated step of fatty acid synthesis?

Answer 4

acetyl coa –> acetyl-CoA carboylase –> malonyl CoA

Question 5

Enlongation of FAs occurs where?

Answer 5

in the ER and mitoc

ER: malonyl coa is the carbo donor
mito: FAs are elongated in a process simliar to reverse B-oxidation

Question 6

Desaturation of FAs occurs where and requires what?

Answer 6

in the ER and requires a p450 MEOS symstem

Question 7

Synthesis of TAG requires what and comes from where?

Answer 7

glycerol; and comes from glycolysis in the well-fed statee

Question 8

What converts DHAP –> glycerolphosphate?

Answer 8

glycerol P dH

Question 9

glycerol + 3 FAS =?

Answer 9

TAG + 3 H2O

Question 10

In the well-fed state, FA and TAG synthesis increase or decrease? WHY?

Answer 10

increase
1. insulin induces expression of acetly-CoA carboxylase, FA synthase, malic enzyme, G6PD

2.

Question 11

Explain AMP dependent kinase levels.

Answer 11

low AMP levels inactivate AMPK, which activates acetyl COA carboxylase and turns on fatty acid synthesis

Question 12

When is HSL active?

Answer 12

in the fasting state.. it gets phosphorylation by PKA which activates HSL; cleavages storage fat and frelease free FAs into circulation