Exam 2 Cell Metabolism

Which of the following enzymes creates 2 phosphoglycerate?

Enolase

If cell charge [ATP/AMP] is high in muscle cells. What is the effect on the glycolysis pathway in those cells?

Phosphofructokinase activity will be decreased

Which of the following is an allosteric inhibitor of Phosphofructokinase?

Proton

Which enzyme is the rate-limiting enzyme of glycolysis?

Phosphofructokinase

What protection does the feedback regulation of hexokinase offer the cell?

Protection from depletion of Pi

What purpose does lactate dehydrogenase serve? Lactate is a dangerous material!

Lactate dehydrogenase helps maintain the activity of glyceraldehyde-3 phosphate dehydrogenase

Which of the following amino acids CANNOT supply carbon for gluconeogenesis? select all that apply

Leucine

Lysine

Why do red blood cells undergo hemolytic anemia in individuals with pyruvate kinase deficiency?

Failure of ATP requiring ion pumps

Which of the following glycolytic enzymatic reactions is freely reversible in cellular conditions?

Glyceraldehyde 3 phosphate to dihydroxyacetone phosphate

Which of the following is an enzyme that is freely reversible in glycolysis?

Phosphoglycerate Kinase

Oxidative damage can be repaired by glutathione. What is needed to restore glutathione?

NADPH

Evaluate the statement below as true or false. If the statement is false, determine if clause A, clause B, or both are erroneous.

(A) Fructose-6 Phosphate can react with Glyceraldehyde-3 phosphate using the enzyme Transketolase.

(B) Xylulose-6-phosphate and Ribose-4-phosphate are produced.

B is false

In the Pentose Phosphate Pathway, which reducing equivalent is generated and what is the primary purpose of that reducing equivalent? select 2 answers

Anabolic Metabolism

NADPH

The pathway is correct

The pentose phosphate shunt, phase 2 produces metabolites that are directly used in what other metabolic pathway?

Glycolysis

A patient presents with memory loss and partial paralysis. There is a syndrome with these symptoms. Metabolically speaking, what is the cause of this?

The malfunctioning enzyme has lost affinity for TPP

A patient presents with a fever and an accompanying bacterial infection. The patient reports no allergies to any medications. Metabolite analysis reveals a below physiological normal amount of Ribulose-5-phosphate. Which of the following medications would be risky to administer to the patients (Select all that apply)

Antipyretic Acetaminophen
Antimalarial Quinones
Sulfa-based antibiotics

Which enzyme in the pentose-phosphate-shunt can generate fructose-6-phosphate? select all that apply

Transketolase

Transaldolase

Which enzyme is the rate limiting step of the Pentose Phosphate Pathway?

Glucose-6 phosphate Dehydrogenase

A patient presents with memory loss and partial paralysis. There is a syndrome with these symptoms. On a hunch, you order a metabolite index for pentose phosphate shunt metabolites. Based on data, it seems like an enzyme is not running forward as fast as it should. Which of the answers provided below is the most likely consequence of this enzyme malfunction?

A substantial decrease in sedoheptulose-7-phosphate

Citrate is an allosteric inhibitor of which enzyme?

Phosphofructosekinase

Carbon Dioxide is often considered a waste product and is one method by which carbon and oxygen are eliminated from metabolic systems. Select the enzymes that produce carbon dioxide.

6-phosphogluconate dehydrogenase
Alpha-ketoglutarate dehydrogenase
Isocitrate dehydrogenase
Pyruvate dehydrogenase

Which TCA enzyme catalyzes the most exergonic reaction in the pathway?

Citrate Synthase

What type of reaction does the enzyme malate dehydrogenase perform?

Oxidation Reduction

What enzyme is the rate-limiting step of the TCA cycle?

Isocitrate Dehydrogenase

How many Toal reducing equivalents (i.e. charged electron carriers) are made in one turn of the TCA cycle?

4

What metabolic material can be used directly to make both Acetyl CoA and Oxaloacetate?

Pyruvate

Which enzyme is considered part of TCA and ETC?

Succinate Dehydrogenase

What enzyme in TCA cycle produces product presumably with a positive delta G?

Malate Dehydrogenase

A patient presents with fatigue and metabolite analysis reveals elevated malate compared to normal samples. Based on this information, which enzyme is likely to be malfunctioning?

Citrate Synthase

Cytochrome C Oxidase produces what product?

Water

Match the complex with its formal name

NADH Ubiquinone —> Complex I

FADH2 Ubiquinone Oxidoreductase —> Complex II

Ubiquinol Cytochrome C Oxidoreductase —> Complex III

Cytochrome C Oxidase —> Complex IV

Select the answer that correctly completed these sentences (not that all sentences relate to each other).

Compound 1 ____ compound 2 by giving electrons to compound 2

Compound 2 is called a(n) _____

Compound 1 is called a(n) ______

Compound 2 ____ compound 1

reduced, oxidant, reductant, oxidized

Which of the following is an electron transport enzyme that cannot pump protons to the inter membrane space of mitochondria?

Succinate Dehydrogenase

What is the primary source of energy for the F1F0 ATP Synthase?

Electrochemical gradient

From one run of the proposed electron transport chain, how many ATP equivalents in energy could theoretically be generated?

4

What is the voltage on the reaction containing the oxidant? (Do not use units)

-0.5

What is the product of oxidation In the proposed chain?

Barsoom

What is the standard free energy of the proposed chain? (Do not use units)

-34.5

What is the reductant in the proposed chain?

Barsool