Question 1

Which of these statements regarding phosphorylation of acetyl-CoA carboxylase is correct?

Accepted Answer

A) Phosphorylation causes activation only in the presence of palmitoyl-CoA. 
B) Phosphorylation is a result of insulin binding to its receptor. 
C) High [citrate] inhibits the phosphorylated form. 
D) Phosphorylation causes separation of the polymeric form of the enzyme to inactive protomers. 
A) Phosphorylation causes activation only in the presence of palmitoyl-CoA. 
B) Phosphorylation is a result of insulin binding to its receptor. 
C) High [citrate] inhibits the phosphorylated form. 
D) Phosphorylation causes separation of the polymeric form of the enzyme to inactive protomers.

Question 2

At what position in fatty acids can mammals introduce double bonds?

Accepted Answer

A) ∆1 
B) ∆3 
C) ∆6 
D) ∆9 
A) ∆1 
B) ∆3 
C) ∆6 
D) ∆9

Question 3

Which of the following compounds is correctly paired with its effect upon fatty acid synthesis?

Accepted Answer

A) palmitoyl CoA: activates 
B) glucagon: activates 
C) insulin: inhibits 
D) citrate: activates 
A) palmitoyl CoA: activates 
B) glucagon: activates 
C) insulin: inhibits 
D) citrate: activates

Question 4

Which of the following is NOT a characteristic of squalene?

Accepted Answer

A) It requires an insoluble protein activator. 
B) It is bound to the endoplasmic reticulum (ER). 
C) It uses FAD and NADPH. 
D) It requires O₂. 
A) It requires an insoluble protein activator. 
B) It is bound to the endoplasmic reticulum (ER). 
C) It uses FAD and NADPH. 
D) It requires O₂.

Question 5

Which of these lipids does NOT have a sphingosine backbone?

Accepted Answer

A) ganglioside GM1 
B) sphingomyelin 
C) phosphatidylinositol 
D) cerebroside 
A) ganglioside GM1 
B) sphingomyelin 
C) phosphatidylinositol 
D) cerebroside

Question 6

Which of the following is NOT a characteristic of eicosanoids?

Accepted Answer

A) They are derived from steric acid. 
B) They exert their effects at very low concentrations. 
C) They usually act very near their site of synthesis. 
D) They include prostaglandins,thromboxanes,and leukotrienes. 
A) They are derived from steric acid. 
B) They exert their effects at very low concentrations. 
C) They usually act very near their site of synthesis. 
D) They include prostaglandins,thromboxanes,and leukotrienes.

Question 7

Which enzyme catalyzes the formation of malonyl-CoA,the committed step in fatty acid biosynthesis?

Accepted Answer

A) fatty acid synthase 
B) pyruvate carboxylase 
C) propionate carboxylase 
D) acetyl-CoA carboxylase 
A) fatty acid synthase 
B) pyruvate carboxylase 
C) propionate carboxylase 
D) acetyl-CoA carboxylase

Question 8

Which compound is NOT an intermediate between mevalonate and squalene?

Accepted Answer

A) geranyl pyrophosphate 
B) isopentenyl pyrophosphate 
C) pyridoxal phosphate 
D) farnesyl pyrophosphate 
A) geranyl pyrophosphate 
B) isopentenyl pyrophosphate 
C) pyridoxal phosphate 
D) farnesyl pyrophosphate

Question 9

What is the series of drugs known as "statins" used for?

Accepted Answer

A) to inhibit fatty acid synthesis in diet drugs 
B) to inhibit squalene monooxygenase 
C) to inhibit HMG-CoA reductase 
D) to lower cholesterol levels 
A) to inhibit fatty acid synthesis in diet drugs 
B) to inhibit squalene monooxygenase 
C) to inhibit HMG-CoA reductase 
D) to lower cholesterol levels

Question 10

Which group is similar to the "business end" of CoA in acyl carrier protein?

Accepted Answer

A) biotin 
B) phosphoadenosine 
C) pyridoxal phosphate 
D) phosphopantetheine 
A) biotin 
B) phosphoadenosine 
C) pyridoxal phosphate 
D) phosphopantetheine

Question 11

What are the carbons of sphinganine derived from?

Accepted Answer

A) palmitate and glycerol 
B) arachidonate and glycine 
C) fatty alcohol and dihydroxyacetone phosphate (DHAP) 
D) palmitate and serine 
A) palmitate and glycerol 
B) arachidonate and glycine 
C) fatty alcohol and dihydroxyacetone phosphate (DHAP) 
D) palmitate and serine

Question 12

Which compound in eukaryotes can phosphatidic acid be directly converted into?

Accepted Answer

A) triacylglycerols 
B) acylglycerols 
C) monoacylglycerols 
D) diacylglycerols 
A) triacylglycerols 
B) acylglycerols 
C) monoacylglycerols 
D) diacylglycerols

Question 13

Which components constitute the core of lipoproteins?

Accepted Answer

A) proteins and triacylglycerols 
B) triacylglycerols and cholesterol esters 
C) phospholipids and cholesterol esters 
D) cholesterol esters and proteins 
A) proteins and triacylglycerols 
B) triacylglycerols and cholesterol esters 
C) phospholipids and cholesterol esters 
D) cholesterol esters and proteins

Question 14

Which of the following is correctly paired with its precursor?

Accepted Answer

A) cholesterol palmitic acid 
B) arachidonic acid prostaglandins 
C) testosterone progesterone 
D) aldosterone cholic acid 
A) cholesterol palmitic acid 
B) arachidonic acid prostaglandins 
C) testosterone progesterone 
D) aldosterone cholic acid

Question 15

Which lipoprotein particle is generated by the action of lipoprotein lipase on VLDL particles?

Accepted Answer

A) HDL 
B) cholesterol esters;LDL 
C) chylomicron 
D) triacylglycerol 
A) HDL 
B) cholesterol esters;LDL 
C) chylomicron 
D) triacylglycerol

Question 16

Which of the following is NOT a characteristic of stearoyl-CoA desaturase?

Accepted Answer

A) requires NADH and O₂ 
B) produces a trans double bond 
C) involves cytochrome b5 reductase 
D) involves cytochrome b5 
A) requires NADH and O₂ 
B) produces a trans double bond 
C) involves cytochrome b5 reductase 
D) involves cytochrome b5

Question 17

Which of these hormones is an intermediate on the biosynthetic pathway from cholesterol to both male and female hormones?

Accepted Answer

A) aldosterone 
B) testosterone 
C) estradiol 
D) progesterone 
A) aldosterone 
B) testosterone 
C) estradiol 
D) progesterone

Question 18

What enzymatic step is NOT involved in the synthesis of mevalonate from acetyl-CoA?

Accepted Answer

A) formation of 3-hydroxy-3-methylglutaryl-CoA 
B) b-ketothiolase-catalyzed condensation 
C) formation of acetyl-CoA 
D) HMG-COA reductase activity 
A) formation of 3-hydroxy-3-methylglutaryl-CoA 
B) b-ketothiolase-catalyzed condensation 
C) formation of acetyl-CoA 
D) HMG-COA reductase activity

Question 19

What is the major circulatory complex for cholesterol and cholesterol esters ("bad cholesterol")?

Accepted Answer

A) chylomicron 
B) HDL 
C) LDL 
D) VLDL 
A) chylomicron 
B) HDL 
C) LDL 
D) VLDL

Exam 9: Lipid Biosynthesis

Which of these statements regarding phosphorylation of acetyl-CoA carboxylase is correct?

At what position in fatty acids can mammals introduce double bonds?

Which of the following compounds is correctly paired with its effect upon fatty acid synthesis?

Which of the following is NOT a characteristic of squalene?

Which of these lipids does NOT have a sphingosine backbone?

Which of the following is NOT a characteristic of eicosanoids?

Which enzyme catalyzes the formation of malonyl-CoA,the committed step in fatty acid biosynthesis?

Which compound is NOT an intermediate between mevalonate and squalene?

What is the series of drugs known as "statins" used for?

Which group is similar to the "business end" of CoA in acyl carrier protein?

What are the carbons of sphinganine derived from?

Which compound in eukaryotes can phosphatidic acid be directly converted into?

Which components constitute the core of lipoproteins?

Which of the following is correctly paired with its precursor?

Which lipoprotein particle is generated by the action of lipoprotein lipase on VLDL particles?

Which of the following is NOT a characteristic of stearoyl-CoA desaturase?

Which of these hormones is an intermediate on the biosynthetic pathway from cholesterol to both male and female hormones?

What enzymatic step is NOT involved in the synthesis of mevalonate from acetyl-CoA?

What is the major circulatory complex for cholesterol and cholesterol esters ("bad cholesterol")?

The Facts of Life: Chemistry Is the Logic of Biological Phenomena

Water: the Medium of Life

Thermodynamics of Biological Systems

Amino Acids

Proteins: Their Primary Structure and Biological Functions

Proteins: Secondary, tertiary, and Quaternary Structure

Carbohydrates and the Glycoconjugates of Cell Surfaces

Lipids

Membranes and Membrane Transport

The Reception and Transmission of Extracellular Information

Enzymes Kinetics and Specificity

Mechanisms of Enzyme Action

Enzyme Regulation

Molecular Motors

Nutrition and the Organization of Metabolism

Glycolysis

The Tricarboxylic Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Gluconeogenesis, glycogen Metabolism, and the Pentose Phosphate Pathway

Fatty Acid Catabolism

Nitrogen Acquisition and Amino Acid Metabolism

Nucleotides and Nucleic Acids

Structure of Nucleic Acids

Synthesis and Degradation of Nucleotides

Recombinant Dna: Cloning and Creation of Chimeric Genes

DNA Metabolism: Replication, recombination, and Repair

Transcription and the Regulation of Gene Expression

Protein Synthesis

Post-Transcriptional Regulation of Gene Expression

Completing the Protein Life Cycle: Folding, processing, and Degradation

Metabolic Integration and Organ Specialization

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