Lipids II Flashcards Preview

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Flashcards in Lipids II Deck (45):
1

citrate cleavage pathway

how excess acetyl-CoA is export4ed from teh mitochondria

2

how does citrate get through the innermitochondrial membrane

tricarbozyl acid transport

3

what happens with citrate gets into the cytopalsm

ATP citrate lyase separates citrate into OAA and acetyl CoA

4

how do you get OAA into the mitochondrial matrix

malate dehydrogeanse and malic enzyme convert into pyruvate and CO2

5

what happens when OAA gets converted into pyruvate and CO2

turns NADH into NADPH

6

what do high cytoplasmic citrate conc indicate

CAC is not able to process all the actyl CoA

7

what does high cytoplasmic citrate trigger

glycolysis slows down
FA synthesis ramps up

8

what is the committed step of malonyl CoA

Acetyl-CoA caarboxylase

9

how does FA synthesis start

transfer of acetyl group for acetyl CoA to acyl carrie rprotein on FA synthase

10

what happens to the acetyl group on FA synthase

moves from A site to C site

11

what happens to the empy A site

malonyl group transfered ther

12

what happens to the acetyl group on the C site

transferred to alpha carbon of teh maloyn group on A site
CO32 released

13

what happens to the acetyl group after its on the alpha carbon

keto group on beta carbon is removed, saturated fatty acids transferred back to C site

14

how many carbons is palmitic acid

16

15

what do you need to make 1 molecule of pamitic acid

8 acetyl CoA
7 ATP
14 NADPH

16

what happens after palmitic acid has been released from FA synthase

linked to CoA and modified by elongation and desautration

17

where does elongation of FA take place

ER or mitochondria

18

what happens to FA in ER

elongated in process similiar to FA syntehsis

19

what happens to FA in mitochondria

FA elongaed in process simliar to reverse beta oxidation

20

what end to elongation of FA take plac

carboxyl end

21

where does destuartion of FA occur

ER

22

what does desaturation of FA require

p450 monoxygenase system

23

whawt carbon can you not make a double bond past

9

24

what are important features of lipid droplets

they are surrounded by phospholipid monolayer
covered with structural proetins
bind to enzymes required for TAG synthesis and degration

25

TAGs

triacyglycerols

26

what are the msot active tissues in fat synthesis

adipose, liver, muscles

27

synthesis of TAGs requires what

glycerol

28

how do activate FA

bind to COenzyme A using ATP

29

what is the committed step of fat synthesis

acyl-COA dicyglycerol acltransferases (DGAT)

30

what are the 3 signals that regulate fat synthesis and degration

nutritional status
engery status
presence of lipids

31

how does insulin affect FA synthesis

induces expression of actyl-CoA carboxylase, FA synthase

32

both fatty acid synthase and actyl CoA carboylase is activated by what

citrate

33

what happens to FA and TAG synthesis in the fasting state

decrease

34

how does cAMP affect FA synthesis

activates PKA, which inactivates acetyl-CoA carboxylase

35

what do high levels of AMP activate

AMPK, which inactivates acetyl-CoA carboxylase

36

how does malonyl-CoA affect FA degration

inhibits

37

what is the main regulated step of FA degration

import of FA into mitochondrion by CPT1

38

what inhibits CPT1

maylonyl CoA

39

what do free fatty acids stimulate

FA degration an dketogensis

40

what do fatty acids bind to

PPARalpha

41

PPARalpha

transcription activater binds to PPRE in promotre region of genes for fatty acid oxidation and ketogensis

42

really of free fatty acids from adipose tissue is regulated by waht

glucagon/insulin ration

43

high glucagon/insulin ration in fasting state leas to what

release of FA from adipose tissue

44

how does glucagon leads to realse of FA from adipose tissue

activation of PKA via cAMP
PKA activates perilipin and hormone sensitive lipiase
lipase cleaves storage fat, reeases free FAs into circulation

45

function of hormone senstive lipase

turns TAG into FFA and glycerol