Fatty Acid Synth

Question 0

2nd C after carboxyl C

Answer 0

beta C

Question 1

1st C after carboxyl C

Answer 1

alpha C

Question 2

last C of chain (furthest from carboxyl C)

Answer 2

omega C

Question 3

Function of fatty acids

Answer 3

components of triacylglycerols (energy storage) and cholesterol esters, phospholipids and sphingolipids (membranes), and precursor to eicosanoids

Question 4

2 sources of FAs

Answer 4

diet and de novo synth in liver (palmitic acid and stearic acid-sat fat)

Question 5

FA synthesis location

Answer 5

cytosol of liver cells

Question 6

step 1 of FA synth

Answer 6

overall: glucose–>citrate

gluc->pyruvate>OAA and acetyl CoA–>citrate

Question 7

citrate can travel….

Answer 7

thru mitochondrial membrane

Question 8

step 2 FA synth

Answer 8

citrate–>acetyl CoA

NADPH formed

Question 9

pyruvate metabolism occurs

Answer 9

in mitochondria

Question 10

Sources of NADPH in FA synth

Answer 10

pentose phosphate pathway

malic enzyme

Question 11

NADPH used as

Answer 11

reducing equivalents

Question 12

Rate limiting step in de novo FA synth (rxn, enzyme, coenzyme)

Answer 12

acetyl CoA–>malonyl CoA

enzyme: acetyl CoA carboxylase
coenzyme: biotin

Question 13

Regulation of RL step of de novo FA synth

Answer 13

thru AMP protein kinase (inhib: glucogon, act: insulin)

allosteric: inhib: palmitoyl CoA, act: citrate

Question 14

Desaturation of newly synthesized FAs

Answer 14

double bonds can be introduced at the 9, 6, 5, or 4 carbon with 4 distinct desaturases

Question 15

Elongation

Answer 15

occurs in ER, NADPH=reducing agent

-involves malonyl CoA, greater than 22 C chains, involved in spermatogenesis

Question 16

Triacylglyceride biosynthesis

Answer 16

liver can use glycerol directly bc it has glycerol kinase

-triacylglyceride is packaged into VLDL in the liver or stored as fat in adipose tissue

Question 17

Dietary triaglycerides are hydrolyzed in the _____ by ______.

Answer 17

intestine by lipases

Question 18

FAs are reesterified in the

Answer 18

enterocyte

Question 19

Triglycerides are packaged into ______ and released into _______.

Answer 19

chylomicrons, circulation

Question 20

Lipoprotein lipase acts on

Answer 20

chylomicrons and VLDL

Question 21

Released FAs are used for

Answer 21

energy by muscles and stored as triglycerides by adipose tissue