(Dr. McLachlin) (Unit B) Topic Note 12

Question 1

When does beta-oxidation occur?

Answer 1

Low glucose conditions

Question 2

Net Reactions:

Beta-Oxidation of fatty acids

Answer 2

Reactants:
* Fatty acids (from triacylglycerols)

Products:
* NADH
* QH2
* Acetyl-CoA

Question 3

Pathway of Glucose:

From Triacylglycerol to Glucose

(in the brain)

Answer 3

1. Adipocyte
2. Bloodstream
3. Liver
4. Bloodstream
5. Brain

1. Adipocyte: Triacylglycerol to Fatty acids and Glycerol
2. Bloodstream: Fatty acids and Glycerol
3. Liver: Glycerol to Glucose
4. Bloodstream: Glucose
5. Brain: Glucose

Question 4

Pathway of Acetyl-CoA:

From Triacyglycerol to Acetyl-CoA

(in muscles)

Answer 4

1. Adipocyte
2. Bloodstream
3. Muscles

1. Adipocyte: Triacyglycerol to Fatty Acids and Glycerol
2. Bloodstream: Fatty Acids
3. Muscles: Fatty Acids to Acetyl-CoA

Additionally, Fatty Acids also go into liver to make Acetyl-CoA

Question 5

Fatty acids get transported into the mitochondrial matrix as what?

Answer 5

Acyl-CoA (N carbons)

Question 6

Net Reactions:

Beta-oxidation of fatty acids in mitochondrial matrix

Answer 6

Reactants:
* Acyl-CoA (2N carbons)
* N-1 Q
* N-1 NAD+
* N-1 CoA

Products:
* N Acetyl-CoA
* N-1 QH2
* N-1 NADH

Question 7

Pathway of Acetyl-CoA:

From Triacylglycerol to Acetyl-CoA (via Ketone Bodies)

(in the brain)

Answer 7

1. Adipocyte
2. Bloodstream
3. Liver
4. Bloodstream
5. Brain

1. Adipocyte: Triacylglycerol to Fatty Acids and Glycerol
2. Bloodstream: Fatty Acids
3. Liver: Fatty Acids to Acetyl-CoA to Ketone Bodies
4. Bloodstream: Ketone Bodies
5. Brain: Ketone Bodies to Acetyl-CoA to CAC

Question 8

When does fatty acid biosynthesis occur?

Answer 8

Under high glucose conditions

Question 9

Where does fatty acid biosynthesis take place? What has to happen due to this?

Answer 9

In the cytosol
* Acetyl CoA has to be transported into the cytosol via Citrate Transport System

Question 10

Net Reactions:

Fatty acid biosynthesis

(for making palmitate)

Answer 10

Reactants:
* 8 Acetyl-CoA
* 14 NADPH
* 7 ATP

Products:
* Palmitate
* 14 NADP+
* 7 ADP
* 7 Pi

Palmitate can make triacylglycerols and membrane lipids

Question 11

What hormones regulate fatty acid metabolism?

Answer 11

Activate:
* Glucagon

Inhibit:
* Insulin

• Insulin: Means there is a lot of glucose, so would either perform glycolysis or fatty acid biosynthesis
• Glucagon: Means there is no glucose for energy, thus requires fatty acid metabolism