Lipids II

Question 1

citrate cleavage pathway

Answer 1

how excess acetyl-CoA is export4ed from teh mitochondria

Question 2

how does citrate get through the innermitochondrial membrane

Answer 2

tricarbozyl acid transport

Question 3

what happens with citrate gets into the cytopalsm

Answer 3

ATP citrate lyase separates citrate into OAA and acetyl CoA

Question 4

how do you get OAA into the mitochondrial matrix

Answer 4

malate dehydrogeanse and malic enzyme convert into pyruvate and CO2

Question 5

what happens when OAA gets converted into pyruvate and CO2

Answer 5

turns NADH into NADPH

Question 6

what do high cytoplasmic citrate conc indicate

Answer 6

CAC is not able to process all the actyl CoA

Question 7

what does high cytoplasmic citrate trigger

Answer 7

glycolysis slows down

FA synthesis ramps up

Question 8

what is the committed step of malonyl CoA

Answer 8

Acetyl-CoA caarboxylase

Question 9

how does FA synthesis start

Answer 9

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

Question 10

what happens to the acetyl group on FA synthase

Answer 10

moves from A site to C site

Question 11

what happens to the empy A site

Answer 11

malonyl group transfered ther

Question 12

what happens to the acetyl group on the C site

Answer 12

transferred to alpha carbon of teh maloyn group on A site

CO32 released

Question 13

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

Answer 13

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

Question 14

how many carbons is palmitic acid

Answer 14

16

Question 15

what do you need to make 1 molecule of pamitic acid

Answer 15

8 acetyl CoA
7 ATP
14 NADPH

Question 16

what happens after palmitic acid has been released from FA synthase

Answer 16

linked to CoA and modified by elongation and desautration

Question 17

where does elongation of FA take place

Answer 17

ER or mitochondria

Question 18

what happens to FA in ER

Answer 18

elongated in process similiar to FA syntehsis

Question 19

what happens to FA in mitochondria

Answer 19

FA elongaed in process simliar to reverse beta oxidation

Question 20

what end to elongation of FA take plac

Answer 20

carboxyl end

Question 21

where does destuartion of FA occur

Answer 21

ER

Question 22

what does desaturation of FA require

Answer 22

p450 monoxygenase system

Question 23

whawt carbon can you not make a double bond past

Answer 23

9

Question 24

what are important features of lipid droplets

Answer 24

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

Question 25

TAGs

Answer 25

triacyglycerols

Question 26

what are the msot active tissues in fat synthesis

Answer 26

adipose, liver, muscles

Question 27

synthesis of TAGs requires what

Answer 27

glycerol

Question 28

how do activate FA

Answer 28

bind to COenzyme A using ATP

Question 29

what is the committed step of fat synthesis

Answer 29

acyl-COA dicyglycerol acltransferases (DGAT)

Question 30

what are the 3 signals that regulate fat synthesis and degration

Answer 30

nutritional status engery status presence of lipids

Question 31

how does insulin affect FA synthesis

Answer 31

induces expression of actyl-CoA carboxylase, FA synthase

Question 32

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

Answer 32

citrate

Question 33

what happens to FA and TAG synthesis in the fasting state

Answer 33

decrease

Question 34

how does cAMP affect FA synthesis

Answer 34

activates PKA, which inactivates acetyl-CoA carboxylase

Question 35

what do high levels of AMP activate

Answer 35

AMPK, which inactivates acetyl-CoA carboxylase

Question 36

how does malonyl-CoA affect FA degration

Answer 36

inhibits

Question 37

what is the main regulated step of FA degration

Answer 37

import of FA into mitochondrion by CPT1

Question 38

what inhibits CPT1

Answer 38

maylonyl CoA

Question 39

what do free fatty acids stimulate

Answer 39

FA degration an dketogensis

Question 40

what do fatty acids bind to

Answer 40

PPARalpha

Question 41

PPARalpha

Answer 41

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

Question 42

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

Answer 42

glucagon/insulin ration

Question 43

high glucagon/insulin ration in fasting state leas to what

Answer 43

release of FA from adipose tissue

Question 44

how does glucagon leads to realse of FA from adipose tissue

Answer 44

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

Question 45

function of hormone senstive lipase

Answer 45

turns TAG into FFA and glycerol