Question 1

Acyl carrier protein has the same ____ group as the "business end" of ____.

Accepted Answer

A)  thiamin; TPP 
B)  biotin; acetyl-CoA carboxylase 
C)  phosphoadenosine; cAMP 
D)  pyridoxal phosphate; vitamin B6 
E)  phosphopantetheine; CoA 
A)  thiamin; TPP 
B)  biotin; acetyl-CoA carboxylase 
C)  phosphoadenosine; cAMP 
D)  pyridoxal phosphate; vitamin B6 
E)  phosphopantetheine; CoA E

Question 2

Which of the following catalyzes the conversion of cholesterol to pregnenolone, the first step in the conversion of cholesterol to steroid based hormones?

Accepted Answer

A)  7-α-hydroxylase 
B)  desmolase 
C)  steroid 5-α-reductase 
D)  aromatase 
E)  17-ketoreductase 
A)  7-α-hydroxylase 
B)  desmolase 
C)  steroid 5-α-reductase 
D)  aromatase 
E)  17-ketoreductase A

Question 3

____ are all derived from 20-carbon fatty acids that are acylated to membrane phospholipids and released by the enzyme ____.

Accepted Answer

A)  Arachidonates; triacylglycerol lipase 
B)  Arachidonates; phospholipase A1 
C)  Eicosanoids; phospholipase A1 
D)  Eicosanoids; phospholipase A2 
E)  Arachidonates; phospholipase A2 
A)  Arachidonates; triacylglycerol lipase 
B)  Arachidonates; phospholipase A1 
C)  Eicosanoids; phospholipase A1 
D)  Eicosanoids; phospholipase A2 
E)  Arachidonates; phospholipase A2 D

Question 4

The reaction catalyzed by ____ is: Citrate + ATP +CoA → acetyl-CoA + ____ + ____.

Accepted Answer

A)  citrate synthase; malate; AMP + Pi 
B)  citrate synthase; OAA; AMP + PPi 
C)  ATP-citrate lyase; OAA; AMP + PPi 
D)  ATP-citrate lyase; OAA; ADP + Pi 
E)  citrate synthase; OAA; ADP + Pi 
A)  citrate synthase; malate; AMP + Pi 
B)  citrate synthase; OAA; AMP + PPi 
C)  ATP-citrate lyase; OAA; AMP + PPi 
D)  ATP-citrate lyase; OAA; ADP + Pi 
E)  citrate synthase; OAA; ADP + Pi

Question 5

The appropriate sequence of intermediates between mevalonate and squalene are:
A.geranyl pyrophosphate
B.isopentenyl pyrophosphate
C.5-phosphomevalonate
D.farnesyl pyrophosphate
E.dimethylallyl pyrophosphate

Accepted Answer

A)  A, C, D, B, E 
B)  C, B, E, A, D 
C)  C, E, A, D, B 
D)  E, C, B, D, A 
E)  B, C, D, A, E 
A)  A, C, D, B, E 
B)  C, B, E, A, D 
C)  C, E, A, D, B 
D)  E, C, B, D, A 
E)  B, C, D, A, E

Question 6

Phosphorylation of regulatory sites on acetyl-CoA carboxylase ____ the affinity for citrate and ____ the affinity for fatty acyl-CoAs requiring ____ levels of fatty acyl-CoAs for inhibition.

Accepted Answer

A)  increases; decreases; low 
B)  decreases; increases; high 
C)  decreases; increases; low 
D)  increases; decreases; high 
E)  none are correct 
A)  increases; decreases; low 
B)  decreases; increases; high 
C)  decreases; increases; low 
D)  increases; decreases; high 
E)  none are correct

Question 7

The formation of acetoacetyl-ACP is catalyzed by:

Accepted Answer

A)  β-ketoacyl-ACP synthase (KSase). 
B)  acetyl-CoA carboxylase. 
C)  acetyl transacylase. 
D)  β-hydroxyacyl dehydratase. 
E)  β-ketoacyl reductase. 
A)  β-ketoacyl-ACP synthase (KSase). 
B)  acetyl-CoA carboxylase. 
C)  acetyl transacylase. 
D)  β-hydroxyacyl dehydratase. 
E)  β-ketoacyl reductase.

Question 8

In E. coli, β-hydroxydecanoyl-ACP is dehydrated by β-hydroxydecanoyl thioester dehydrase to form a double bond ____ to the thioester in the ____ configuration which is further elongated to form ____.

Accepted Answer

A)  α,β; cis; palmitoyl-ACP 
B)  β,γ; cis; palmitoleoyl-ACP 
C)  β,γ; trans; palmitoleoyl-ACP 
D)  α,β; trans; palmitoleoyl-ACP 
E)  β,γ; cis; palmitoyl-ACP 
A)  α,β; cis; palmitoyl-ACP 
B)  β,γ; cis; palmitoleoyl-ACP 
C)  β,γ; trans; palmitoleoyl-ACP 
D)  α,β; trans; palmitoleoyl-ACP 
E)  β,γ; cis; palmitoyl-ACP

Question 9

The coenzyme(s) of acetyl-CoA carboxylase is/are:

Accepted Answer

A)  biotin and NAD+. 
B)  TPP. 
C)  NADH and FAD. 
D)  TPP and folic acid. 
E)  biotin. 
A)  biotin and NAD+. 
B)  TPP. 
C)  NADH and FAD. 
D)  TPP and folic acid. 
E)  biotin.

Question 10

Platelet-activating factor displays dramatic ability to ____ blood vessels and thus ____ blood pressure, and to aggregate platelets.

Accepted Answer

A)  dilate; reduce. 
B)  dilate; reduce 
C)  constrict; increase./ 
D)  constrict; increase. 
E)  constrict; increase 
A)  dilate; reduce. 
B)  dilate; reduce 
C)  constrict; increase./ 
D)  constrict; increase. 
E)  constrict; increase

Question 11

Lipoproteins consist of a core of ____ and ____ surrounded by a single layer of ____, into which is inserted ____ and ____.

Accepted Answer

A)  proteins; triacylglycerols; cholesterol esters; phospholipids; cholesterol 
B)  triacylglycerols; cholesterol esters; phospholipids; proteins; cholesterol 
C)  phospholipids; cholesterol esters; triacylglycerols; proteins; cholesterol 
D)  cholesterol esters; proteins; cholesterol; phospholipids; triacylglycerols 
E)  triacylglycerols; cholesterol; proteins; cholesterol esters; phospholipids 
A)  proteins; triacylglycerols; cholesterol esters; phospholipids; cholesterol 
B)  triacylglycerols; cholesterol esters; phospholipids; proteins; cholesterol 
C)  phospholipids; cholesterol esters; triacylglycerols; proteins; cholesterol 
D)  cholesterol esters; proteins; cholesterol; phospholipids; triacylglycerols 
E)  triacylglycerols; cholesterol; proteins; cholesterol esters; phospholipids

Question 12

Stearoyl-CoA desaturase has all of the following characteristics EXCEPT:

Accepted Answer

A)  NADH and O2 are required. 
B)  produces a trans double bond. 
C)  involves cytochrome b5 reductase. 
D)  involves cytochrome b5. 
E)  occurs in the endoplasmic reticulum. 
A)  NADH and O2 are required. 
B)  produces a trans double bond. 
C)  involves cytochrome b5 reductase. 
D)  involves cytochrome b5. 
E)  occurs in the endoplasmic reticulum.

Question 13

All are regulatory mechanisms of HMG-CoA reductase EXCEPT:

Accepted Answer

A)  low [cholesterol] increases mRNA for HMG-CoA reductase. 
B)  high [cholesterol] increases half-life for HMG-CoA reductase. 
C)  high [cholesterol] results in lower mRNA for HMG-CoA reductase. 
D)  phosphorylation by cAMP cascade inactivates HMG-CoA reductase. 
E)  phosphatases activate HMG-CoA reductase. 
A)  low [cholesterol] increases mRNA for HMG-CoA reductase. 
B)  high [cholesterol] increases half-life for HMG-CoA reductase. 
C)  high [cholesterol] results in lower mRNA for HMG-CoA reductase. 
D)  phosphorylation by cAMP cascade inactivates HMG-CoA reductase. 
E)  phosphatases activate HMG-CoA reductase.

Question 14

Sphinganine is acylated in the ____-position.

Accepted Answer

A)  3-OH 
B)  2-NH2 
C)  1-OH 
D)  3-NH2 
E)  all are true 
A)  3-OH 
B)  2-NH2 
C)  1-OH 
D)  3-NH2 
E)  all are true

Question 15

Discuss the functions of glucocorticoids.​

Accepted Answer

​Glucocorticoids are a class of steroid

Question 16

Male baldness, prostate hyperplasia and prostate cancer have been implicated in elevated levels of ____ and treatment involves inhibition of ____.

Accepted Answer

A)  glucocorticoids; gluconeogenesis 
B)  stanozolol; lactate dehydrogenase 
C)  dihydrotestosterone; steroid 5α-reductase 
D)  cholesterol; mevinolin 
E)  none of the above 
A)  glucocorticoids; gluconeogenesis 
B)  stanozolol; lactate dehydrogenase 
C)  dihydrotestosterone; steroid 5α-reductase 
D)  cholesterol; mevinolin 
E)  none of the above

Question 17

In fatty acid synthase, the correct sequence of enzyme catalyzed reactions are:
A.β-ketoacyl-ACP synthase
B.β-ketoacyl reductase
C.β-hydroxyacyl dehydratase
D.enoyl reductase
E.acetyl transferase

Accepted Answer

A)  A, B, C, D, E 
B)  C, B, D, E, A 
C)  B, A, C, D, E 
D)  A, C, B, E, D 
E)  D, E, A, B, C 
A)  A, B, C, D, E 
B)  C, B, D, E, A 
C)  B, A, C, D, E 
D)  A, C, B, E, D 
E)  D, E, A, B, C

Question 18

Dietary lipids are "packaged" in the intestine into ____ for transport via the lymphatic system.

Accepted Answer

A)  chylomicrons 
B)  HDL 
C)  IDL 
D)  VLDL 
E)  LDL 
A)  chylomicrons 
B)  HDL 
C)  IDL 
D)  VLDL 
E)  LDL

Question 19

There is no transporter for acetyl-CoA to exit the mitochondria, so the carbons must be converted to ____ for transport to the cytosol.

Accepted Answer

A)  acetone 
B)  butyrate 
C)  citrate 
D)  pyruvate 
E)  malonate 
A)  acetone 
B)  butyrate 
C)  citrate 
D)  pyruvate 
E)  malonate

Question 20

Which of the following 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 glucagon 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 
E)  both b and d are true 
A)  phosphorylation causes activation only in the presence of palmitoyl-CoA 
B)  phosphorylation is a result of glucagon 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 
E)  both b and d are true

Exam 24: Lipid Biosynthesis

Acyl carrier protein has the same ____ group as the "business end" of ____.

Which of the following catalyzes the conversion of cholesterol to pregnenolone, the first step in the conversion of cholesterol to steroid based hormones?

____ are all derived from 20-carbon fatty acids that are acylated to membrane phospholipids and released by the enzyme ____.

The reaction catalyzed by ____ is: Citrate + ATP +CoA → acetyl-CoA + ____ + ____.

The appropriate sequence of intermediates between mevalonate and squalene are: A.geranyl pyrophosphate B.isopentenyl pyrophosphate C.5-phosphomevalonate D.farnesyl pyrophosphate E.dimethylallyl pyrophosphate

Phosphorylation of regulatory sites on acetyl-CoA carboxylase ____ the affinity for citrate and ____ the affinity for fatty acyl-CoAs requiring ____ levels of fatty acyl-CoAs for inhibition.

The formation of acetoacetyl-ACP is catalyzed by:

In E. coli, β-hydroxydecanoyl-ACP is dehydrated by β-hydroxydecanoyl thioester dehydrase to form a double bond ____ to the thioester in the ____ configuration which is further elongated to form ____.

The coenzyme(s) of acetyl-CoA carboxylase is/are:

Platelet-activating factor displays dramatic ability to ____ blood vessels and thus ____ blood pressure, and to aggregate platelets.

Lipoproteins consist of a core of ____ and ____ surrounded by a single layer of ____, into which is inserted ____ and ____.

Stearoyl-CoA desaturase has all of the following characteristics EXCEPT:

All are regulatory mechanisms of HMG-CoA reductase EXCEPT:

Sphinganine is acylated in the ____-position.

Discuss the functions of glucocorticoids.​

Male baldness, prostate hyperplasia and prostate cancer have been implicated in elevated levels of ____ and treatment involves inhibition of ____.

In fatty acid synthase, the correct sequence of enzyme catalyzed reactions are: A.β-ketoacyl-ACP synthase B.β-ketoacyl reductase C.β-hydroxyacyl dehydratase D.enoyl reductase E.acetyl transferase

Dietary lipids are "packaged" in the intestine into ____ for transport via the lymphatic system.

There is no transporter for acetyl-CoA to exit the mitochondria, so the carbons must be converted to ____ for transport to the cytosol.

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

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

Water: the Medium of Life

Thermodynamics of Biological Systems

Amino Acids and the Peptide Bond

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

Nucleotides and Nucleic Acids

Structure of Nucleic Acids

Recombinant Dna, Cloning, Chimeric Genes, and Synthetic Biology

Enzymeskinetics and Specificity

Mechanisms of Enzyme Action

Enzyme Regulation

Molecular Motors

Metabolism: an Overview

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

Synthesis and Degradation of Nucleotides

Metabolic Integration and Organ Specialization

Dna Metabolism: Replication, Recombination, and Repair

Transcription and the Regulation of Gene Expression

Protein Synthesis

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

The Reception and Transmission of Extracellular Information

Filters

Acyl carrier protein has the same group as the "business end" of .

are all derived from 20-carbon fatty acids that are acylated to membrane phospholipids and released by the enzyme .

The reaction catalyzed by is: Citrate + ATP +CoA → acetyl-CoA + + .

Phosphorylation of regulatory sites on acetyl-CoA carboxylase the affinity for citrate and the affinity for fatty acyl-CoAs requiring levels of fatty acyl-CoAs for inhibition.

In E. coli, β-hydroxydecanoyl-ACP is dehydrated by β-hydroxydecanoyl thioester dehydrase to form a double bond to the thioester in the configuration which is further elongated to form .

Platelet-activating factor displays dramatic ability to blood vessels and thus blood pressure, and to aggregate platelets.

Lipoproteins consist of a core of and surrounded by a single layer of , into which is inserted and .

Discuss the functions of glucocorticoids.

Male baldness, prostate hyperplasia and prostate cancer have been implicated in elevated levels of and treatment involves inhibition of .