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| 1 |
Go |
Q:
|
Which of the following accurately describes anaerobic respiration? |
|
A
|
It requires H2O as a terminal electron acceptor |
B
|
It cannot function in the presence oxygen |
C
|
It is only found among chemotrophs |
D
|
It can function without oxygen |
|
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Tags:
Glycolysis, Gluconeogenesis, PPP | |
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| 2 |
Go |
Q:
|
Of the tissues listed below, which ones break down glycogen when stimulated by glucagon?
I. Liver
II. Muscle
III. Brain |
|
A
|
I only |
B
|
I and II |
C
|
III only |
D
|
I, II, and III |
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|
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Tags:
Glycolysis, Gluconeogenesis, PPP | |
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| 3 |
Go |
Q:
|
Which of the following best explains why glycolysis AND gluconeogenesis are characterized by irreversible processes in cells? |
|
A
|
The processes occur in separate cellular compartments |
B
|
All of the enzymes in both pathways are different, so the reaction pathways do not overlap |
C
|
Key reactions in each pathway are characterized by large, negative changes in free energy |
D
|
The processes are triggered by the same irreversibly-binding hormones |
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Tags:
Glycolysis, Gluconeogenesis, PPP | Enzyme Structure and Function | |
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| 5 |
Go |
Q:
|
The primary structural difference between starch and glycogen is that
|
|
A
|
starch is a polymer of sucrose while glycogen is a polymer of glucose |
B
|
glycogen is more branched than starch |
C
|
starch is produced by plants while glycogen is produced by animals |
D
|
there is no difference between glycogen and starch |
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|
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Tags:
Glycolysis, Gluconeogenesis, PPP | |
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| 7 |
Go |
Q:
|
Clostridium botulinum is a common soil bacterium. Unlike some other obligate anaerobes, C. botulinum is able to survive in the presence of oxygen with the help of certain metabolic antioxidants. Which of the following enzymes would you expect to find in C. botulinum that you would not find in non-aerotolerant anaerobes? |
|
A
|
pyruvate dehydrogenase (pyruvate → acetyl CoA) |
B
|
carbonic anhydrase (CO2 + H2O ↔ H2CO3) |
C
|
superoxide dismutase (O2- → H2O2) |
D
|
monoamine oxidase (RCH2NH2 ↔ RCHO) |
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Tags:
Glycolysis, Gluconeogenesis, PPP | Prokaryotes | |
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| 8 |
Go |
Q:
|
The MAJOR reason that aerobes cannot live in the absence of oxygen is that |
|
A
|
The Citric Acid cycle needs to oxidize oxygen in order to complete its reaction |
B
|
Glycolysis will not run in the absence of oxygen |
C
|
The ETC uses oxygen as its final electron acceptor |
D
|
All of the above |
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Tags:
Glycolysis, Gluconeogenesis, PPP | Oxidative Phosphorylation | |
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| 9 |
Go |
Q:
|
Which of the following conditions would be present in an oxygen-starved cell of an aerobic organism? |
|
A
|
an excess of NADH |
B
|
an excess of NAD+ |
C
|
an excess of ATP |
D
|
an excess of oxidative radicals |
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Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 10 |
Go |
Q:
|
In the absolute absence of the Krebs cycle and other forms of oxidative phosphorylation, how many net moles of ATP can be formed from 1 mole of glucose? |
|
A
|
0 moles |
B
|
2 moles |
C
|
4 moles |
D
|
8 moles |
|
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Tags:
Glycolysis, Gluconeogenesis, PPP | |
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| 11 |
Go |
Q:
|
Muscle fibers come in two generic types: fast twitch and slow twitch. Fast twitch fibers contract quickly and fatigue quickly as well - they rely mainly on glycolytic mechanisms for energy production. Slow twitch muscle relies upon aerobic activity for energy. Which of the following metabolytes would not be expected to be produced in fast twitch muscle metabolism? |
|
A
|
Pyruvate |
B
|
ADP |
C
|
CO2 |
D
|
1,3-bisphosphoglycerate |
|
|
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Tags:
Glycolysis, Gluconeogenesis, PPP | Musculoskeletal System | |
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| 12 |
Go |
Q:
|
Mature red blood cells have hemoglobin and no organelles. These cells metabolize glucose, which generates lactate, and can be used by the liver in gluconeogenesis. Which of the following does NOT explain why mature red blood cells metabolize glucose to lactate in order to generate energy? |
|
A
|
Anaerobic oxidation of pyruvate regenerates the NAD+ required for glycolysis to continue |
B
|
Oxygen is not available for the aerobic oxidation of glucose |
C
|
Mature red blood cells have no citric acid cycle |
D
|
Mature red blood cells have no mitochondria |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | Circulatory System | Citric Acid Cycle | |
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| 13 |
Go |
Q:
|
A PET (Positron Emission Tomography) scan typically uses fludeoxyglucose, a synthetic radioactive glucose analog that is imported into cells but cannot be metabolized until after radioactive decay. On a scan image, regions of high radioactivity would directly be indicative of |
|
A
|
high volume of blood flow. |
B
|
high rate of cell division. |
C
|
high metabolic activity. |
D
|
high rate of apoptosis. |
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|
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Tags:
Carbohydrates | Glycolysis, Gluconeogenesis, PPP | |
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| 14 |
Go |
Q:
|
Which of the following is true of glycogen and glucose within the body? |
|
A
|
The liver is the largest store of glycogen. |
B
|
Muscle stores glycogen but the liver is the main organ which is capable of increasing circulating glucose. |
C
|
Muscle can break down glycogen to release glucose into the bloodstream. |
D
|
The enzyme phosphofructokinase is a key enzyme in breaking down glycogen and releasing glucose into the bloodstream. |
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|
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Tags:
Glycolysis, Gluconeogenesis, PPP | |
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| 15 |
Go |
Q:
|
Which of the following does NOT help describe the distinction between ketogenic and glucogenic amino acids?
|
|
A
|
Ketogenic amino acids undergo an aminotransferase reaction and are combined to yield acetyl-CoA
|
B
|
Ketogenic amino acids are catabolized to yield acetyl-CoA
|
C
|
Glucogenic amino acids are catabolized to intermediates that serve as substrates for gluconeogenesis, such as pyruvate
|
D
|
Glucogenic amino acids can be converted into glucose through gluconeogenesis
|
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|
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Tags:
Glycolysis, Gluconeogenesis, PPP | Metabolism of Fatty Acids and Proteins | |
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| 16 |
Go |
Q:
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Which of the following is NOT correct regarding the maximum number of ATPs produced per molecule of aerobically oxidized glucose?
|
|
A
|
NADH influences the maximum number of ATPs since it cannot cross the inner mitochondrial membrane.
|
B
|
The maximum number of ATPs does not depend on the "shuttle system" used. |
C
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Using the malate shuttle to translocate electrons produced by glycolysis for oxidative phosphorylation results in 2.5 ATP per NADH.
|
D
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Using the glycerol 3-phosphate shuttle to translocate electrons produced by glycolysis for oxidative phosphorylation results in 1.5 ATP per NADH. |
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Tags:
Glycolysis, Gluconeogenesis, PPP | Oxidative Phosphorylation | |
|
| 17 |
Go |
Q:
|
Glucocorticoids both block the activity of insulin and stimulate gluconeogenesis. Which of the following would be an expected effect of glucocorticoid use? |
|
A
|
elevated blood sugar levels |
B
|
increased basal metabolic rate |
C
|
increased sensitivity to immunological challenge |
D
|
increased bone density |
|
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Tags:
Glycolysis, Gluconeogenesis, PPP | Hormonal Regulation | |
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| 19 |
Go |
Q:
|
A hypothetical weight-loss drug inhibits ATP Synthase. Which of the following best describes why this drug could possibly help with weight loss? |
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A
|
Due to the drug inhibiting ATP Synthase, glucose cannot be broken down, and is therefore excreted
|
B
|
The drug blocks ATP metabolism, requiring the person to break down the energy stored in their fat reserves
|
C
|
Due to the drug inhibiting ATP Synthase, more glucose is used because less ATP can be made per molecule
|
D
|
The drug causes cells to use far less ATP than normal, so they use less glucose
|
|
|
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Tags:
Enzyme Structure and Function | Glycolysis, Gluconeogenesis, PPP | |
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| 21 |
Go |
Q:
|
Which of the following best describes the effect of insulin secretion from the pancreas immediately after a meal? |
|
A
|
A decreased rate of glucose transport into the target cell
|
B
|
An increased rate of glucose transport into the target cell
|
C
|
A decreased rate of glucose utilization and ATP generation
|
D
|
A decreased conversion of glucose to glycogen in liver and skeletal muscle
|
|
|
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Tags:
Glycolysis, Gluconeogenesis, PPP | Membrane Transport and Signalling | |
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| 22 |
Go |
Q:
|
The liver and muscle both play crucial roles in glycogen breakdown, but there are differences between the two. For example, muscle cells lack the enzyme glucose-6-phosphatase, which is required to pass glucose into the blood. Which of the following is FALSE regarding glycogen metabolism? |
|
A
|
Although the muscle stores large amounts of glycogen, the liver is the major source of circulating glucose.
|
B
|
Only the glycogen stored in the liver can be made accessible to other organs in the body
|
C
|
While the muscle stores large amounts of glycogen, it lacks an enzyme to break down glycogen and release large amounts of glucose into circulation
|
D
|
While the liver stores large amounts of glycogen, it lacks an enzyme to break down glycogen and release large amounts of glucose into circulation
|
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|
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Tags:
Glycolysis, Gluconeogenesis, PPP | Enzyme Structure and Function | |
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| 23 |
Go |
Q:
|
During the first step of glucose metabolism, an enzyme drives catalysis and binds glucose in its active site. A second site exists (away from the active site) which binds ATP (the eventual end-product of glucose metabolism). Which of the following is NOT correct in describing the mechanism behind the ATP-binding site on this enzyme? |
|
A
|
The ATP-binding site is an example of feedback inhibition
|
B
|
ATP acts as a non-competitive inhibitor of the enzyme.
|
C
|
The enzyme is less active when ATP is present in high concentrations
|
D
|
The enzyme is more active when ATP is present in high concentrations
|
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|
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Tags:
Enzyme Structure and Function | Glycolysis, Gluconeogenesis, PPP | |
|
| 24 |
Go |
Q:
|
Which of the following correctly describes a situation when cells switch from respiration to fermentation? |
|
A
|
When pyruvate is no longer available
|
B
|
When electron acceptors are no longer available
|
C
|
When NADH and FADH2 are in low quantity
|
D
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When the proton-motive force is decreasing
|
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | Oxidative Phosphorylation | |
|
| 26 |
Go |
Q:
|
After Glycolysis and the Citric Acid Cycle (Kreb's Cycle), most of the energy from the original glucose molecule is now in the form of what? |
|
A
|
Pyruvate |
B
|
ATP |
C
|
H2O
|
D
|
High-energy electrons associated with electron carriers
|
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|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | Citric Acid Cycle | |
|
| 27 |
Go |
Q:
|
Which of the following correctly describes where glucagon stimulates the release of glucose? |
|
A
|
Adipose tissue |
B
|
Skeletal tissue |
C
|
Thyroid gland |
D
|
Liver |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 30 |
Go |
Q:
|
Which of the following is NOT correct in regard to alanine and amino acid catabolism?
|
|
A
|
Alanine cannot be formed from the initial breakdown of glucose during glycolysis
|
B
|
Alanine is utilized and transported to the liver (from the muscles) during amino acid catabolism
|
C
|
Alanine is formed from pyruvate in the muscles
|
D
|
Alanine's reconstitution in the liver results in the production of urea
|
|
|
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Tags:
Protein Structure and Function | Metabolism of Fatty Acids and Proteins | Glycolysis, Gluconeogenesis, PPP | |
|
| 31 |
Go |
Q:
|
Which of the following is NOT correct regarding the control and regulation of gluconeogenesis? |
|
A
|
The control of gluconeogenesis is inversely linked to the control of glycolysis
|
B
|
Glucagon stimulates adenylyl cyclase, which causes cAMP formation
|
C
|
Most of the enzymes responsible for the control and regulation of gluconeogenesis are found in the cytoplasm
|
D
|
Acetyl-CoA only activates gluconeogenesis enzymes and has no inhibitory role in gluconeogenesis
|
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|
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Tags:
Enzyme Structure and Function | Glycolysis, Gluconeogenesis, PPP | Control of Enzyme Activity | |
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| 33 |
Go |
Q:
|
Which of the following processes are used by red blood cells in mammals?
I. Glycolysis
II. Citric acid cycle
III. Electron transport chain |
|
A
|
I only
|
B
|
I and II only |
C
|
II and III only |
D
|
I and III only |
|
|
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Tags:
Circulatory System | Glycolysis, Gluconeogenesis, PPP | |
|
| 35 |
Go |
Q:
|
The pentose phosphate pathway differs from glycolysis in that: |
|
A
|
the pentose phosphate pathway occurs in the mitochondria while glycolysis occurs in the cytosol.
|
B
|
the pentose phosphate pathway produces NAD+ while glycolysis produces NADH.
|
C
|
the pentose phosphate pathway produces a precursor for the synthesis of fatty acids while glycolysis produces a precursor for the oxidation of fatty acids.
|
D
|
the pentose phosphate pathway starts with the oxidation of glucose-6-phosphate while glycolysis starts with the oxidation of glucose.
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|
|
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Tags:
Glycolysis, Gluconeogenesis, PPP | Metabolism of Fatty Acids and Proteins | |
|
| 36 |
Go |
Q:
|
The pentose phosphate pathway would be upregulated by excess of which of the following? |
|
A
|
NADH |
B
|
NADP+ |
C
|
FAD+ |
D
|
Acetyl-CoA |
|
|
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Tags:
Glycolysis, Gluconeogenesis, PPP | |
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| 37 |
Go |
Q:
|
Which of the following best characterizes the difference between NADH and NADPH? |
|
A
|
NADH is generally used for catabolic pathways while NADPH is generally used for anabolic pathways. |
B
|
NADH is reduced while NADPH is oxidized. |
C
|
NADH is produced in the Krebs cycle while NADPH is produced in glycolysis. |
D
|
NADPH is used in phosphorylation reactions while NADH is used in dephosphorylation reactions. |
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|
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Tags:
Glycolysis, Gluconeogenesis, PPP | Miscellaneous Biochemistry | |
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| 40 |
Go |
Q:
|
The pentose phosphate pathway is primarily utilized for production of: |
|
A
|
NADPH. |
B
|
NADH. |
C
|
NAD+. |
D
|
glyceraldehyde 3-phosphate. |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 41 |
Go |
Q:
|
Glucose is converted to various sugar molecules through glycolysis. Which of the following correctly lists one of these sugar molecules within the glycolytic pathway? |
|
A
|
Fructose 1-Phosphate |
B
|
Fructose 6-Phosphate |
C
|
Fructose 3,6-Bisphosphate |
D
|
Sucrose 1-Phosphate |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 42 |
Go |
Q:
|
Which of the following is the rate-limiting enzyme in glycolysis? |
|
A
|
glycogen synthase |
B
|
lactate dehydrogenase |
C
|
glucose-6-phosphate dehydrogenase |
D
|
phosphofructokinase-1 |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 44 |
Go |
Q:
|
A defect in which of the following pathways would most likely affect the production of ribose 5-phosphate in the body? |
|
A
|
Krebs cycle |
B
|
pentose phosphate pathway |
C
|
gluconeogenesis |
D
|
glycolysis |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 45 |
Go |
Q:
|
Which of the following steps of glycolysis utilize ATP?
I. conversion of glucose to glucose 6-phosphate
II. conversion of fructose 6-phosphate to fructose 1,6-bisphosphate
III. conversion of fructose 1,6-bisphosphate to glyceraldehyde 3-phosphate |
|
A
|
I only |
B
|
I and II only |
C
|
II only |
D
|
I, II, and III |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 46 |
Go |
Q:
|
Acetyl-CoA is made from the product of which of the following pathways? |
|
A
|
glycolyis |
B
|
citric acid cycle |
C
|
pentose phosphate pathway |
D
|
glycogenolysis |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 48 |
Go |
Q:
|
Which of the following are products of glycolysis?
I. NADH
II. ATP
III. pyruvic acid |
|
A
|
I and III only |
B
|
III only |
C
|
I and II only |
D
|
I, II and III |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
| 50 |
Go |
Q:
|
Which of the following is a false statement regarding glycolysis? |
|
A
|
Glycolysis occurs in the cytoplasm. |
B
|
Activation of glycolysis requires 2 ATP. |
C
|
1 Glucose and 2 NAD+ molecules are the reactants of glycolysis. |
D
|
Glycolysis produces 2 molecules of pyruvic acid, 3 molecules of NADH, and 4 molecules of ATP. |
|
|
|
Tags:
Glycolysis, Gluconeogenesis, PPP | |
|
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