november 10

Question 1

how do adipose cells mkae glycerol 3 phosphate

Answer 1

they dont have glycerol kinase so they make DHAP using glyceroneogenesis

Question 2

where does glyceroneogenesis occur

Answer 2

in adipose tissue and liver

Question 3

glyceoneogenesis and gluconeogenesis

Answer 3

contains some of the same steps, it converts pyruvate to DHAP instead of maknig glucose so it is just a condensed version in liver and adipose.

Question 4

what enzyme makes Glycerol 3 phosphate from DHAP

Answer 4

glycerol 3 phosphate dehydrogenase

Question 5

what stimulates triacylglycerol sytnehsis

Answer 5

insulin

Question 6

what does lack of insulin lead to

Answer 6

increased lipolysis
increased fatty acid oxidation and ketone body formation
failure to synthesize FA

Question 7

what is not present in adipose tissue

Answer 7

glycerol kinase

Question 8

phospholipid structure

Answer 8

uses a glycerol backbone with 2 FA and one phosphate that is linked to a head group

Question 9

R1 of phospholipids

Answer 9

almost always saturated FA

Question 10

R2 of phospholipids

Answer 10

almost always unsaturated

Question 11

what plays a role in being an integral compoent of cell membranes, storage of FA, and signalling molecules wihtin cells

Answer 11

phospholipids

Question 12

what does phospholipid synthesis begin with

Answer 12

phosphatidic acid or diacylglycerol

Question 13

synthesis of phospholipids step by step

Answer 13

attatch head group which has OH to C3 OH leading to a new phosphohead group created when phosphoric acid condences wit these two alcohols

elimination of 2 water molecules

Question 14

what does the catabolism of phospholipids include

Answer 14

the hydrolysis of FA or head groups by a group of enzymes known as phospholipases (PLase)

Question 15

what are the phospholipases

Answer 15

A1, A2, C, D

Question 16

what do PLase do

Answer 16

essential for providing several critical molecules involved in the regulation of various cell activities

Question 17

what do PLase A1, A2 do

Answer 17

liberate a single FA from PL and generate a lysophospholipid (PC to LPC)

Question 18

what contains PLaseA1 and PLaseA2

Answer 18

toxic snake venoms that cause cell membrane damage

Question 19

what phospholipase do mammals use

Answer 19

A2

Question 20

how do mammals use A2

Answer 20

release arachidonic acid (20:4n-6) FROM THE SN-2 position of PLs

the released arachidonic acid is rapidly enzymatically modified to produce eicosanoids

Question 21

what do eicosanoids do

Answer 21

potent lipid signaling molecules involved in regulating many physiological events including reproduction, inflamation, pain, fever, blood pressure

Question 22

what does omega 3 FA do

Answer 22

inhibit the production of omega 6 FA dervied from eicosanoids (omega 6 are inglamatory and omega 3 are anti inflamatory(

Question 23

what does PLase C do

Answer 23

liberates phosphoheadgroup (phosphocholine) and diacylglycerol from PL

diacyl glycerol liberated by PLaseC functions as a potent intracellular signalling molecules that regulate Ca2+ concentration

Question 24

what does PLaseD do

Answer 24

converts a phoshpatidylcholine, phoshpatidyl serine, phosphatidyl ehtanolamine or phosphatidylinositol into phosphatidi acid

the acid produced through this route can be used towards the synthesis of triacylglycerol