Exam 21: Lipid Biosynthesis

If malonyl-CoA is synthesized from ¹⁴CO₂ and unlabeled acetyl-CoA,and the labeled malonate is then used for fatty acid synthesis,the final product (fatty acid)will have radioactive carbon in:

Show the reaction that limits the rate of cholesterol synthesis from acetate,indicating the role of any cofactors that participate.

Which of these compounds is not synthesized by a pathway that includes isoprene precursors?

Which of these statements about cholesterol synthesis is true?

All glycerol-containing phospholipids are synthesized from:

Which of the following is not true of the fatty acid elongation system of vertebrate cells?

The synthetic compound mevinolinic acid,also called lovastatin,is a potent competitive inhibitor of HMG-CoA reductase (hydroxymethylglutaryl-CoA reductase).Predict and explain the effect of this drug on serum cholesterol levels in humans.

Which of the following is not true of the fatty acid synthase and the fatty acid $\beta$ -oxidation systems?

If you start with acetyl-CoA labeled with ¹⁴C in the methyl-carbon,where does the label end up in malonyl-CoA?

The synthesis of cholesterol begins with the condensation of a four-carbon unit from _______________ with the two carbons of acetyl-CoA to form a six-carbon derivative.Give its structure,and circle the atoms that originated in the acetyl-CoA.

A strategy that is not employed in the synthesis of phospholipids is:

CDP-diglyceride is not involved in the biosynthesis of:

Which of these statements about eicosanoid synthesis is true?

Which of the following is not a step in the uptake of cholesterol from the bloodstream into cells?

In the synthesis of phosphatidylcholine from phosphatidylethanolamine,the methyl group donor is:

Describe two basic strategies for activating precursors in the biosynthesis of phospholipids.

Which of these statements about triacylglycerol synthesis is correct?

Palmitoyl-CoA,,is a direct precursor of:

In comparing fatty acid biosynthesis with $\beta$ oxidation of fatty acids,which of the following statements is incorrect?

Which of the following is not true of the reaction producing malonyl-CoA during fatty acid synthesis?