Fatty Acid Metabolism

Question 1

What are chylomicrons?

Answer 1

lipoproteins that consist of fats that transport fat via the lymphatic system and bloodstream to organs

Question 2

How are triglycerides broken down into free fatty acids?

Answer 2

hydrolysis reaction

Question 3

What type of reaction do free fatty acids undergo to break down for energy?

Answer 3

beta-oxidation

Question 4

Where does beta-oxidation occur?

Answer 4

mitochondrial matrix

Question 5

What has to occur to free fatty acids in order to be transported into the mitochondrion for beta-oxidation?

Answer 5

must be activated by acyl-CoA synthetase which requires the investment of 2 ATP

Question 6

What is a basic summary of beta-oxidation?

Answer 6

cleaving of a two-carbon acetyl-CoA from the fatty acid to produce 1 NADH and 1 FADH2
process repeats until entire chain is cleaved

Question 7

How is beta-oxidation of unsaturated fatty acids different?

Answer 7

when cleavage reaches the double bond must bring in an isomerase to rearrange the bond for further cleave
**if multiple double bonds then it requires an isomerase and reductase

Question 8

What is ketogenesis?

Answer 8

liver generates ketone bodies in the mitochondrial matrix during periods of starvation when all glycogen stores have been exhausted

Question 9

What are the ketone bodies?

Answer 9

acetone, acetoacetate, and beta-hydroxybutyrate

Question 10

What are the ketone bodies generated from?

Answer 10

acetyl-CoA

Question 11

What is the purpose of ketone bodies?

Answer 11

they can pass the blood brain barrier, turn back into acteyl-CoA and enter the Krebs Cycle providing energy to the brain

Question 12

What is catabolism?

Answer 12

the breakdown of a substance

Question 13

What is anabolism?

Answer 13

the synthesis of a substance

Question 14

Where does fatty acid synthesis take place?

Answer 14

cytoplasm

Question 15

What is a basic description of fatty acid synthesis?

Answer 15

repeated addition of two-carbon subunits to a the desired chain length (16-carbon)

Question 16

What is the first step in fatty acid synethesis?

Answer 16

activation of acetyl-CoA in a carboxylation reaction facilitated by acetyl-CoA carboxylase forming malonyl-CoA

Question 17

What is the committed step of fatty acid synthesis and what does it require?

Answer 17

activation of acetyl-CoA to form malonyl-CoA
requires investment of ATP

Question 18

What enzyme is responsible for the addition of two-carbon subunits during fatty acid synthesis?

Answer 18

fatty acid synthase

Question 19

What is the ACP?

Answer 19

acyl carrier protein

Question 20

What are the two main domains on fatty acid synthase?

Answer 20

ACP and cysteine residue domain

Question 21

What is required for reducing the newly formed X-carbon unit on fatty acid synthase?

Answer 21

NADPH from the pentose phosphate pathway

Question 22

Which domain does the new malonyl-CoA bind to on fatty acid synthase?

Answer 22

ACP

Question 23

What are modification that can be made to the 16-carbon chain made from fatty acid synthase?

Answer 23

elongation and addition of functional groups