BIOC 406 Lecture Notes - Lecture 4: Acetyl-Coa Carboxylase, Carnitine O-Palmitoyltransferase, Palmitoyl-Coa

49 views6 pages

ochreporcupine180

12 Jan 2017

School

Department

Biochemistry

Course

BIOC 406

Professor

Peter Brzovic

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Breakdown of sugar, fats, and amino acids a lot of these can filter in to form. After a meal in particular, when your energy state is high and you have a lot of metabolic precursors, you don"t need to generate a lot of energy. Therefore it can be used to synthesize fats and cholesterol. One of the key important steps for the use of acetyl-coa comes with acetyl- Coa carboxylase, which is in the cytosol, and catalyzes the conversion of acetyl-coa to malonyl-coa, the committed step of fatty acid synthesis and the main control point. After a meal, the pancreas recognizes the fed state and starts to secrete insulin. The dephosphorylated form of acetyl-coa carboxylase is active, and the phosphorylated form is inactive. That way, you don"t get a lot of malonyl-coa for fatty acid synthesis. If glucose levels drop, the liver will start to regulate blood sugar and ramp up gluconeogenesis.

Related Questions

16- When the body is deficient in oxaloacetate

a) acetyl CoA from the b-oxdiation pathway cannot enter the citric acid cycle

b) oxaloacetate is diverted to gluconeogenesis

c) acetyl CoA is diverted to form the ketone bodies

d) all of the above are true

e) none of the above

17- The synthesis of ketone bodies involves

a) synthesis of acetoacetyl-CoA by reversal of the thiolase reaction of fatty oxidation

b) synthesis of b-hydroxy-b-methylglutaryl-CoA (HMG-CoA)

c) cleavage of HMG-CoA to acetoacetate.

d) b-Hydroxybutyrate is produced by reduction of acetoacetate.

e) all of the above

18- Which of the statements about ketone body production is FALSE?

a) Ketone bodies are produced when there is more acetyl-CoA in the liver than can be oxidized in the citric acid cycle.

b) Ketone bodies production is not a normal process, and occurs only in diabetes or starvation

c) The ketone bodies produced in the body are the free acids and not the CoA esters.

d) When fatty acid oxidation in the liver is uncontrolled, ketone body production becomes excessive and life-threatening because these acidic compounds lower the pH of blood

e) When fatty acid oxidation

19- In which of the following ways can the 4-carbon compound acetoacetyl CoA produced in fatty acid degradation be further metabolized?

a) It can break down further to form acetyl CoA,

b) It can be converted to the ketone bodies

c) It can be used for synthesis of cholesterol and its many derivÂatives.

d) It can do all of the above

e) It can do none of the above

20- Acetyl CoA from the beta-oxidation pathway cannot enter the citric acid cycle in which of these circumstances?

a) periods of fasting

b) periods of starvation

c) diabetes

d) when the body is deficient in oxaloacetate

e) all of the above

taupemarten625

30. In final step of the triacylglycerol biosynthesis, which of the following is added to the diacylglycerol?

A. Acetyl-CoA

B. Phosphatidic acid

C. Fatty acyl-CoA

D. Glycerol-3-P

31. The activation of long chain fatty acids requires which of the following?

A. 2 ATPs

B. 2 ATPs and Co-A

C. 2 ATP, CoA and fatty-acyl CoA

D. 2 ATPs and a fatty acid.

32. What is the metabolic pathway that does not involve succinyl-CoA?

A. Ketone bodies to acetyl CoA

B. Odd chain fatty acid oxidation

C. Even chain fatty acid oxidation

D. TCA cycle

33. In order to break down fatty acids, they are first transported into the mitochondrial matrix by conversion of the fatty acid from a covalent complex with CoA to one with:

A. Citrate.

B. Oxaloacetate.

C. Malate.

D. Carnitine.

E. Pyruvate.

34. Regarding carnitine shuttle, the enzyme translocase involves which of the following pair?

A. Fatty acyl & CoA

B. Fatty acyl-carnitine & carnitine

C. Fatty acyl CoA & carnitine

D. Fatty acyl & carnitine

35. The family of drugs that are called "statins" (e.g. lipitor) are effective at lowering plasma levels of cholesterol because they:

A. slow the rate of cholesterol uptake from plasma into the cell.

B. increase the rate of synthesis of cholesterol inside the cell.

C. inhibit the activity of a key enzyme in the cholesterol synthetic pathway.

D. prevent the synthesis of Mevalonate

1. preparing a fatty acid to be catabolized through beta oxidation involves all of these except:

A. expenditure of 2 ATP equivalents.

B. attachment to carnitine.

C. crossing from the matrix into the cytosol through a translocase.

D. attachment to Coenzyme A

2. Ketone body formation

A. produces a water-insoluble fuel for brain cells.

B. occurs only under starvation conditions.

C. takes place in the cytosol.

D. allows acetyl CoA to be made into net glucose.

E. is favored when the citric acid cycle is inhibited.

3. Which statement concerning fatty acid synthesis is false?

A. Fatty acid synthesis from acetyl CoA requires ATP hydrolysis.

B. Fatty acid synthesis requires acetyl CoA to leave the matrix in the form of citrate.

C. Fatty acid synthesis takes place on a multifunctional enzyme complex.

D. Fatty acid synthesis is regulated at the carnitine transporter.

4. Cholesterol is transported from peripheral tissues to the liver as

A. chylomicrons.

B. VLDLs.

C. IDLs.

D. LDLs.

E. HDLs.

The most common route for a nitrogen atom removed from a branched amino acid in muscle tissue to formation of urea is

A. branched AA --> glutamate--> glutamine --> carbamoyl phosphate --> urea

B. branched AA --> alanine--> aspartate --> glutamine --> urea

C. branched AA --> aspartate--> alanine --> glutamate --> glutamine --> urea

D. branched AA Ã alanineÃ glutamate Ã carbamoyl phosphate Ã urea

E. branched AA Ã glutamateÃ arginine Ã carbamoyl phosphate Ã urea

teallizard787

BIOC 406 Lecture Notes - Lecture 4: Acetyl-Coa Carboxylase, Carnitine O-Palmitoyltransferase, Palmitoyl-Coa

Document Summary

Get access

Related Documents

BIOC 406 Lecture Notes - Lecture 2: Malonyl-Coa, Pyruvate Carboxylase, Acetyl-Coa

BIOC 406 Lecture Notes - Lecture 10: Diabetic Retinopathy, Urea Cycle, Pyruvate Carboxylase

BIOC 406 Lecture Notes - Lecture 3: Leaving Group, Acyltransferase, Succinic Acid

Related Questions