Intro to lipids and their metabolism

Question 1

major storage form of metabolic energy

Answer 1

triglycerides

Question 2

Three reasons for storing energy as fat

Answer 2

1. lower oxidation state = more nrg per gram
2. anhydrous = more nrg per gram
3. anhydrous = don’t affect osmotics = stored as large fraction of cell’s volume (lots of room for storage)

Question 3

why are the double bonds in polyunsaturated fats neither adjacent nor oxidixed

Answer 3

too easily oxidized

Question 4

glycerol

Answer 4

esterified version of fatty acids

Question 5

what is the only organ that can’t use non-esterified fatty acids as fuel

Answer 5

brain

Question 6

two sources of NEFA

Answer 6

dietary fat (TG), FA synthesized de nuovo

Question 7

how are dietary fats (TGs) made accessible

Answer 7

exogenous pathway

Question 8

how are fatty acids synthesized de nuovo made available

Answer 8

endogenous pathway

Question 9

where are fatty acids made de nuovo

Answer 9

liver, adipose cells

Question 10

C14

Answer 10

• DB = 0
• acid = mystric
• salt = mystrate
• D = 14:0
• w n/a

Question 11

C16, 0 double bonds

Answer 11

• acid = palmitic
• salt = palmitate
• D = 16:0
• w = n/a

Question 12

C16, 1 double bond

Answer 12

• acid = palmitoleic
• salt = palmitoleate
• D = 16:1D9
• w = 16:1w-7

Question 13

C18 0 double bonds

Answer 13

• acid = stearic
• salt = stearate
• D = 18:0
• w = n/a

Question 14

C18 1 double bond

Answer 14

• acid = oleic
• oleate
• D = 18:1D9
• w = 18:1w-9

Question 15

C18 2 double bonds

Answer 15

• acid = a-linoleic
• salt = linoleiate
• D = 18:2D9,12
• w = 18:2w-6

Question 16

C18, 3 double bonds

Answer 16

• acid = linolenic
• salt = linolenate
• D = 18:3D9,12,15
• w = 18:3w-3

Question 17

C20 4 double bonds

Answer 17

• acid = arachadonic
• salt = arachadonate
• D = 20:4D5,8,11,14
• w = 20:4w-6

Question 18

form of fatty acids used most as fuel

Answer 18

non-esterified

Question 19

what is acetyl coA derived from

Answer 19

fatty acids

Question 20

what does acetyl coA yield in the CAC

Answer 20

ATP, heat

Question 21

components of bile

Answer 21

bile acids, phosphatidyl choline, cholestrol

Question 22

enzyme for hydrolysis of ester bonds in TGs

Answer 22

lipase

Question 23

activation of pancreatic lipase

Answer 23

complex with colipase and a droplet of emulsified lipid

Question 24

bile salts (activate/inactivate) lipase

Answer 24

inactivate

Question 25

lipase is what type of enzyme

Answer 25

esterase

Question 26

products of cleavage with lipase

Answer 26

2-monoacylglycerol (2-MAG) and NEFA

Question 27

how are lipids absorbed into intestinal wall

Answer 27

- incorporated into mixed micelles | - then free FA, MAG, and glycerol diffuse or are transported

Question 28

in a mixed micelle, MAG and NEFA are oriented

Answer 28

inside - nonpolar

Question 29

in a mixed micelle, glycerol backbone is oriented

Answer 29

toward aq phase

Question 30

FA transporter in enterocytes

Answer 30

FATP5

Question 31

glycerol transporter

Answer 31

AQP3

Question 32

bile acids are reabsorbed into

Answer 32

enterohepatic recirculation

Question 33

bile salts (enter fat-absorbing enterocytes/stay in duodenal lumen)

Answer 33

stay in duodenal lumen

Question 34

once in the enterocytes, TGs

Answer 34

are resynthesized from 2-MAG and LCFAs, | packaged into cylomicrons

Question 35

lipoprotein particles

Answer 35

chylomicrons

Question 36

what enzymes do enterocytes use to resynthesize TGs from 2-MAG and LCFAs

Answer 36

- acyl CoA synthetase (thinokinase) | - acyltransferases (transacylases)

Question 37

what sizes fatty acids are normally found in feces

Answer 37

small chain

Question 38

which sizes of fatty acids require lipase for digestions

Answer 38

LCFAs only

Question 39

how are SCFAs and MCFAs absorbed

Answer 39

diffuse through enterocytes without prior enzymatic digestion; bypass hydrolysis and resynthesis

Question 40

principle protein of nascent chilomicrons

Answer 40

Apo-B48

Question 41

lipoprotein lipase

Answer 41

releases FAs from chylomicrons

Question 42

products of lipoprotein lipase

Answer 42

glycerol, NEFA

Question 43

effect of lipoprotein lipase in VLDL

Answer 43

releases FAs

Question 44

apoprotein added to chylomicron, recognized by lipoprotein lipase

Answer 44

CII

Question 45

hormone that promotes lipoprotein lipase release from adipocytes and muscle

Answer 45

insulin