Chapter 16 Biochem

The first intermediate formed from glucose in the pentose phosphate pathway is A. 6-phosphogluconolactone B. 6-phosphogluconate C. Fructose 6-phosphate D. Ribulose 5-phosphate E. Glucose 1-phosphate

A. 6-phosphogluconolactone

The hexose monophosphate shunt pathway is utilized for all of the following EXCEPT A. Formation of ATP B. Generation of NADPH C. Ribose-5- phosphate synthesis D. Ribose 5-phosphate degradation E. Synthesis of pentoses

A. Formation of ATP

All of the following are products or intermediates if the hexose monophosphate shunt (pentose phosphate pathway) EXCEPT A. Glucuronic acid 1-phosphate B. Carbon dioxide C. Glyceraldehyde-3- phosphate D. NADPH E. Ribose-5- phosphate

A. Glucuronic acid 1-phosphate

The nonoxidative branch of the pentose phosphate pathway predominates over the oxidative branch when A. More ribose-5- phosphate than NADPH is required B. The needs for NADPH and ribose 5-phosphate are balanced C. More NADPH than ribose 5-phosphate is required D. More NADPH than sedoheptulose 7-phosphate is required

A. More ribose-5- phosphate than NADPH is required

What is a major function of the hexose monophosphate shunt? A. Produce pentoses B. Produces ADP C. Produces NADH D. Pathway for glucuronic acid synthesis

A. Produce pentoses

Which of the following is not a function of the pentose phosphate pathway? A. Provide NAD+ for the oxidation of fatty acids B. Provide NADPH for the synthesis of fatty acids and cholesterol C. Provide Ribose-5- Phosphate for the synthesis of nucleotides D. All of the above are functions of the pentose phosphate pathway

A. Provide NAD+ for the oxidation of fatty acids

All the following occur in the hexose monophosphate pathway for glucose metabolism EXCEPT A. Reduction of NAD B. Formation of C-7 Sugar phosphates C. Formation of C-5 sugar phosphate precursor of nucleotides D. Release of C-1 of glucose as carbon dioxide E. Reduction of NADP

A. Reduction of NAD

which group of compound are all intermediates in the hexose monophosphate shunt A. Sedoheptulose 7-phosphate, glucose 6-phosphate, xylulose 5-phosphate B. Erythrose 4-phosphate, glucose 1 -phosphate, glycerol 3-phosphate. C. Fructose 6-phosphate, fructose 1-phosphate, fructose 1,6-bisphosphate D. Glucose 1-phosphate, erythrose-4- phosphate, carbon dioxide E. Ribulose 5-phosphate ,ribose 1-phosphate , glucose 6-phosphate

A. Sedoheptulose 7-phosphate, glucose 6-phosphate, xylulose 5-phosphate

Thiamine pyrophosphate participates in the reaction catalyzed by A. Transketolase B. Transaldolase C. Pyruvate carboxylase D. Isocitrate dehydrogenase E. Aspartate aminotransferase(GOT).

A. Transketolase

All of the following statements about the phosphogluconate (pentose phosphate) pathway are correct EXCEPT which one? A. A carbohydrate containing 7 carbon atoms can be produced by this pathway. B. Containing 5 carbon atoms are absent from this pathway C. A major product of the pathway is NADPH. D. The pathway is important in red blood cells because a product of the pathway is required for maintaining the proper oxidation-reduction state. E. A key enzyme in the pathway is glucose 6-phosphate- dehydrogenase

B. Containing 5 carbon atoms are absent from this pathway

All of the following are reactants of products of the phosphate pathway for glucose oxidation EXCEPT A. Certain triose phosphates B. FADH2 C. Glucose 6-phosphate D. CO2 E. A certain 7 carbon sugar

B. FADH2

Which of the following generates NADPH? A. Glycolysis B. Hexose monophosphate shunt C. Krebs Cycle D. Gluconeogenesis E. Glycogenolysis

B. Hexose monophosphate shunt

Glucose 6-phosphate dehydrogenase catalyzes the first step in which of the following pathways? A. Glycolysis B. Pentose phosphate pathway C. Gluconeogenesis D. Tricarboxylic acid cycle E. Glycogen synthesis

B. Pentose phosphate pathway

The enzyme transketolase is a component of A. The TCA cycle B. The Hexose Monophosphate Shunt(HMP) C. Fatty acid synthase D. The pyruvate dehydrogenase complex E. None of the above

B. The Hexose Monophosphate Shunt(HMP)

The enzyme transaldolase is a component of A. The TCA cycle B. The hexose monophosphate shunt C. Fatty acid synthase D. The pyruvate dehydrogenase complex E. None of the above

B. The hexose monophosphate shunt

All of the following are accomplished by the hexose monophosphate shunt EXCEPT A. Hexose may be converted to pentose B. Glucose-6- phosphate may be synthesized from pentose phosphates C. A major source of energy is supplied to the body via oxidation of NADPH by the electron transport chain. D. Pentoses may be converted into glycolytic intermediates and then to pyruvate.

C. A major source of energy is supplied to the body via oxidation of NADPH by the electron transport chain

Carbon number 1 of glucose in the hexose monophosphate shunt is converted to A. Ribose B. Deoxyribose C. Carbon Dioxide D. Fatty acid

C. Carbon Dioxide

Which of the following best indicates the products of the hexose monophosphate shunt? A. NAD and pyruvate B. The oxidized form of NADPH C. Carbon dioxide and NADPH D. NADH and pentoses E. ATP, pentoses and carbon dioxide

C. Carbon dioxide and NADPH

The oxidative branch of the pentose phosphate pathway predominates over the nonoxidative branch when A. More ribose 5-phosphate than NADPH is required. B. The needs for NADPH and ribose 5-phosphate are balanced C. More NADPH than ribose 5 phosphate is required D. More sedoheptulose 7-phosphate than NADPH is required.

C. More NADPH than ribose 5 phosphate is required

The products of the pentose phosphate pathway include A. NAD+ and pyruvate B. NADH and pentose phosphate C. NADPH and carbon Dioxide D. ATP, pentose phosphate and carbon dioxide

C. NADPH and carbon Dioxide

The products of the pentose phosphate pathway include A. NAD+ and pyruvate B. NADH and pentose phosphate C. NADPH and carbon dioxide D. ATP,pentose phosphate and carbon dioxide.

C. NADPH and carbon dioxide

Pentose Phosphate pathway occurs in A. Nucleus B. Nucleus/ribosomes C. cytosol D. mitochondria

C. cytosol

All of the following are intermediates in the conversion of glucose to ribose EXCEPT A. 6-phosphogluconate B. D-ribulose- 5-phosphate C. Ribose-5- phosphate D. Glucose-1- phosphate E. Glucose -6- phosphate

D. Glucose-1- phosphate

All of the following molecules are formed in the pentose phosphate pathway EXCEPT A. Carbon Dioxide B. Pentose 5-phosphate C. NADPH D. NADH E. Glyceraldehyde 3- phosphate

D. NADH

The hexose monophosphate shunt is least active in A. liver B. Adipose tissue C. Red blood cells D. Skeletal muscle E. Gonads and adrenal tissue

D. Skeletal muscle (and muscles in general)

The non-oxidation portion of the hexose monophosphate shunt A. Forms CO2 as glucose-6- phosphate is converted to pentose phosphate B. Requires ATP C. Converts lactate to pyruvate D. Does not function in mature erythrocytes E. Can lead to synthesis of hexose phosphates from pentose phosphates

E. Can lead to synthesis of hexose phosphates from pentose phosphates

In glucose 6-phosphate dehydrogenase deficiency, the associated hemolytic anemia is ultimately due to what changes from normal in red cells? A. A decreased formation of ATP by mitochondria B. Decreased ability to carry out glycolysis C. Increased leakage of potassium into the cells D. An intrinsic defect in membrane structure E. Decreased concentrations of NADPH

E. Decreased concentrations of NADPH

All of the following are directly associated with the pentose phosphate pathway EXCEPT A. Fructose 6-phosphate B. Production of pentose phosphates C. Synthesis of NADPH D. Glyceraldehyde-3- phosphate E. Glycerol 3-phosphate

E. Glycerol 3-phosphate

All of the following are products or intermediates of the hexose monophosphate pathway EXCEPT A. Carbon Dioxide B. 6-Phosphogluconate C. Ribulose 5-phosphate D. A 4-carbon sugar phosphate E. NADH

E. NADH

Which of the following is NOT found as an intermediate or product of the pentose phosphate pathway? A. NADPH B. Ribulose 5-phosphate C. Xylulose 5-phosphate D. Ribose-5- phospahte E. NADH

E. NADH

The principal regulatory factor governing the rate of the pentose phosphate pathway if the level of A. ATP B. ADP C. AMP D. NAD+ E. NADP+

E. NADP+

The immediate products of oxidation of one mole of glucose 6-phosphate through the oxidative portion of the pentose phosphate pathway are A. One mole of ribulose 5-phosphate, one mole of carbon dioxide and reduction of two moles of NAD. B. One mole of ribulose 5-phosphate , one mole of carbon dioxide and oxidation of two moles of NADPH. C. One mole of xylulose-5- phosphate, one mole carbon dioxide and reduction of two moles of NADPH D. One mole of ribose-5 phosphate, one mole carbon dioxide and reduction of two moles of NADPH E. One mole of fructose-6- phosphate and reduction of two mole of NADP

E. One mole of fructose-6- phosphate and reduction of two mole of NADP

In liver, the hexose monophosphate shunt is the principal source of A. Carbon Dioxide B. Glucose 6-phosphate C. The reduction of NAD D. Fructose 6-phosphate E. Ribose-5- phosphate

E. Ribose-5- phosphate

The carbohydrate used in the synthesis of nucleic acids in animals is produced in A. The urea cycle B. Glycolysis C. The citric acid cycle D. Electron transport E. The hexose monophosphate pathway

E. The hexose monophosphate pathway

Erythrose 4-phosphate + fructose 6-phosphate ←→ sedoheptulose 7- phosphate+glyceraldehyde 3-phosphate. This reaction is catalyzed by A. Transaminase B. Transhydrogenase C. Transketolase D. Transamidinase E. Transaldolase

E.Transaldolase