METABOLISM AND ENERGY PRODUCTION Flashcards
The common metabolic pathway:
A. Glycolysis
B. Beta oxidation
C. Kreb’s Cycle
D. Glucogenesis
C. Kreb’s Cycle
It is regarded as the universal biological energy currency:
A. ATP
B. GTP
C. cAMP
D. UTP
E. cGMP
A. ATP
It is a metabolic process occurring at the “cross roads: of metabolism (citric acid cycle):
A. Anabolic
B. Catabolic
C. Amphibolic
D. All of the choices
C. Amphibolic
Glycolysis produces ____ ATPs:
A. 2
B. 6
C. 36
D. 32
A. 2
The common product of carbohydrate, protein and fat catabolism is:
A. Glucose
B. Amino acids
C. Acetyl CoA
D. Fatty acids
C. Acetyl CoA
The final product of glycolysis is:
A. Pyruvate
B. Oxaloacetate
C. Citrate
D. Acetyl CoA
A. Pyruvate
Glucogenesis involves the formation of glucose from:
A. Non – carbohydrate sources
B. Pentose
C. Aldohexose
D. Ketohexose
E. Polysaccharides
A. Non – carbohydrate sources
The conversion of an amino acid to sugar is
A. Gluconeogenesis
B. Glycolysis
C. Glycogenesis
D. Glycogenolysis
E. Glucogenesis
A. Gluconeogenesis
Glucose, amino acid and fatty acid enter the citric acid cycle by their conversion into:
A. Pyruvate
B. Acetyl CoA
C. Malonyl CoA
D. Palmitic acid
B. Acetyl CoA
Gluconeogenesis is the formation of new glucose. The enzymes responsible for this are only confined to some organs, which includes:
A. Muscles
B. Liver
C. Kidneys
D. A and B
E. B and C
E. B and C
The term “anaerobic phase” of glucose oxidation is used to designate series of reaction known as:
A. Glycolysis
B. Glycogenesis
C. Glycogenolysis
D. Both A and B
A. Glycolysis
What enzyme in gluconeogenesis is employed to bypass the hexokinase reaction, which is the interconversion of glucose to glucose – 6 – phosphate?
A. Pyruvate carboxylase
B. PEP carboxykinae
C. Fructose biphosphatase
D. Glucose – 6 – phosphatase
D. Glucose – 6 – phosphatase
The pentose phosphate pathway occurs in the ____ of liver, muscle and kidney
A. Inner mitochondria
B. Outer mitochondria
C. Cytosol
D. Ribosomes
E. Tissues
C. Cytosol
Which of the following is/are the main goals of Pentose Phosphate Pathway?
A. Produce ribose – 5 – Phosphate for nucleotide synthesis
B. Produce NADPH and NADP for fatty acid and steroid biosynthesis
C. To interconvert pentose and hexoses
D. All of these
E. A and B only
D. All of these
Which of the following enzymes is present only in the liver and kidney and not in the muscle?
A. Pyruvate carboxylase
B. PEP carboxykinase
C. Fructose biphosphatase
D. Glucose – 6 - phosphatase
D. Glucose – 6 - phosphatase
This refers to aldose – ketose interconversion:
A. Tautomerization
B. Isomerism
C. Mutarotation
D. Conjugation
A. Tautomerization
This is the only reaction coupled with substrate level phosphorylation in the TCA.
A. Citrate to isocitrate
B. Isocitrate to alpha – ketoglutarate
C. Succinyl CoA to succinate
D. Succinate to fumarate
C. Succinyl CoA to succinate
This is the only reaction in TCA that involves FAD/FADH2?
A. Citrate to isocitrate
B. Isocitrate to alpha – ketoglutarate
C. Succinyl CoA to succinate
D. Succinate to fumarate
D. Succinate to fumarate
How many ATPs are produced for every acetyl CoA oxidized?
A. 10
B. 12
C. 14
D. 8
E. 6
B. 12
How many ATPs are produced in the reduction of one mole of NAD to NADH?
A. 2
B. 3
C. 4
D. 12
E. 8
B. 3
How many ATPs are produced in the conversion of one mole of FADH2 to FAD?
A. 2
B. 3
C. 4
D. 12
E. 8
A. 2
The total net ATP produced in aerobic glycolysis is ________ ATPs per mole of hexose, depending on which shuttle predominates in the transport of NAD/NADH.
A. 4 to 6
B. 6 to 8
C. 4 to 8
D. 8 to 10
B. 6 to 8
Which of the following occur(s) in the cytosol?
A. TCA
B. Glycolysis
C. PPP
D. A and B
E. B and C
E. B and C
The condition that lowers the pH of the blood due to starvation is called ____:
A. Acidosis
B. Alkalosis
C. Hyperglycemia
D. Glycosuria
A. Acidosis
The chief end product of purine metabolism:
A. Carbon dioxide
B. Ammonia
C. Urea
D. Uric acid
D. Uric acid
This substance accumulates in the muscle as a result of vigorous exercise:
A. Lactulose
B. Amino acid
C. Glycogen
D. Lactic acid
D. Lactic acid
Which substance yields the largest number of calories per gram?
A. Carbohydrates
B. Proteins
C. Minerals
D. Fats
E. Vitamins
D. Fats
How many ATPs can one molecule of palmitic acid can be yielded via beta-oxidation?
A. 128
B. 129
C. 130
D. 131
E. 132
B. 129
The enzymes involved in ethanol metabolism:
A. Phosphorylase
B. Dehydrogenase
C. Lipase
D. Ketase
E. Thiokinase
B. Dehydrogenase
Amino acids that are not immediately incorporated into new protein are:
A. Stored in the muscles
B. Stored in the liver
C. Recycled in the blood
D. Stored in tissues
E. Rapidly degraded
E. Rapidly degraded
Most nitrogenous waste is converted to urea because:
I. Ammonia and uric acid are toxic
II. Urea is highly soluble
III. Urea is non toxic
A. I only
B. III only
C. II and III
D. I and III
E. I, II and III
E. I, II and III
A number of catabolic pathways are allosterically inhibited by an increase in the concentration of which of the following?
A. ADP
B. AMP
C. ATP
D. NAD+
E. Pyruvate
C. ATP
Which of the following represents the chemical substance that is the immediate source of energy for muscle contraction?
A. Glycogen
B. Acetyl CoA
C. Lactic acid
D. Creatine phosphate
E. Adenosine triphosphate
E. Adenosine triphosphate
The tricarboxylic acid cycle is initiated by the condensation of which of the following two molecules?
A. Pyruvate and malate
B. NAD+ and oxaloacetate
C. NAD+ and oxalosuccinate
D. Acetyl coenzyme A and oxaloacetate
E. Acetyl coenzyme A and oxalosuccinate
D. Acetyl coenzyme A and oxaloacetate
Acids found in the citric acid (Krebs) cycle are:
A. Glutamic acid and succinic acid
B. Glucuronic acid and aspartic acid
C. Oxaloacetic acid and aspartic acid
D. Oxaloacetic acid and pyruvic acid
E. Oxaloacetic acid and α-ketoglutaric acid
E. Oxaloacetic acid and α-ketoglutaric acid
If protein is catabolized for energy, then MOST of the energy is derived from which of the following?
A. Urea production
B. Oxidative deamination
C. Transamination reactions
D. Cleavage of peptide bonds
E. Oxidation of α-keto acids derived from amino acids
E. Oxidation of α-keto acids derived from amino acids
After prolonged acidosis, which of the following represents the nitrogenous product that is excreted in high amounts in the urine?
A. Urea
B. Ammonia
C. Uric acid
D. Creatinine
E. Aspartic acid
B. Ammonia
Excessive utilization of fats by the body as a source of energy during disturbances in carbohydrate metabolism can lead to all of the following conditions, except:
A. Ketosis
B. Acidosis
C. Ketonuria
D. Alkalosis
D. Alkalosis
The final step in the complete metabolism of fat is carried out by means of:
A. Anaerobic glycolysis
B. Tricarboxylic acid cycle
C. Reductive fixation of CO2
D. Hexose monophosphate shunt
E. Krebs-Henseleit (urea) cycle
B. Tricarboxylic acid cycle
Which of the following is necessary for de novo synthesis of cholesterol?
A. NAD+
B. NADH
C. NADP+
D. NADPH
E. FADH2
D. NADPH
Ribose phosphate needed for nucleic acid synthesis can be derived from:
A. Gluconeogenesis
B. Pentose phosphate pathway
C. Krebs’ tricarboxylic acid cycle
D. Decarboxylation of aromatic amino acids
E. One-carbon transfer from tetrahydrofolate derivatives
B. Pentose phosphate pathway
The pathway of extramitochondrial synthesis of even-numbered fatty acids differs from that of the catabolism of fatty acids in that:
A. Malonyl CoA is an intermediate in synthesis
B. Acyl carrier protein is needed in catabolism
C. No flavoprotein enzymes are required for catabolism
D. Propionyl CoA may serve as an intermediate in synthesis
A. Malonyl CoA is an intermediate in synthesis
After functioning in the small intestines, the largest portion of bile salts are:
A. excreted in the feces
B. reabsorbed into the central lacteal
C. destroyed by bacteria in the large intestines
D. reabsorbed into the portal circulation and reused
E. removed from the circulation by the kidneys and excreted in the urine
D. reabsorbed into the portal circulation and reused
Which of the following mechanisms operates in liver cells to regulate breakdown of glycogen?
A. Zymogen activation
B. Phosphorylation of phosphorylase b to phosphorylase a
C. Induction of phosphorylase b by an inducer
D. Inhibition of adenylate cyclase
B. Phosphorylation of phosphorylase b to phosphorylase a
Each of the following is expected to be active during fatty acid biosynthesis, except:
A. Tricarboxylic acid cycle
B. Pyruvate dehydrogenase
C. Amino acid catabolism
D. Beta oxidation
E. Glycolysis
D. Beta oxidation
Symptoms of photophobia/photosensitivity are most likely associated with which metabolic disorder?
A. Phenylketonuria
B. Alkaptonuria
C. Albinism
D. Maple syrup urine disease
C. Albinism
Which of the following is a ketone body?
A. Glycerol
B. Glucagon
C. Acetyl CoA
D. Acetoacetate
E. Phosphatidycholine
D. Acetoacetate
