Question 1

Choose the correct answer from the list below. Not all of the answers will be used. -________________: Pyruvate is decarboxylated at this active site in PDH. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

Pyruvate is decarboxylated at the E1 active site in the pyruvate dehydrogenase (PDH) complex.

Question 2

A deficiency in the vitamin thiamine causes the disease ____________.

Accepted Answer

Beriberi

Question 3

PDH is inactivated when it the enzyme is __________________.

Accepted Answer

phosphorylated

Question 4

Choose the correct answer from the list below. Not all of the answers will be used. -In the presence of oxygen, pyruvate is converted to ________________. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

In the presence of oxygen, pyruvate is converted to acetyl CoA, which then enters the citric acid cycle for further energy production.

Question 5

E₁ of the PDH complex requires the coenzyme __________________ for proper activity.

Accepted Answer

The answer of E₁ of the PDH complex requires the...

Question 6

Choose the correct answer from the list below. Not all of the answers will be used. -________________ is caused by a deficiency in vitamin B1. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

Beriberi is caused by a deficiency in vitamin B1, also known as thiamine.

Question 7

E₂ of the PDH complex contains a lipoyl group that is covalently attached to a __________________ residue of the enzyme.

Accepted Answer

The answer of E₂ of the PDH complex contains a...

Question 8

__________________ is the PDH subunit responsible for the regeneration of the oxidized form of lipoamide.

Accepted Answer

The answer of __________________ is the PDH subunit responsible for...

Question 9

Choose the correct answer from the list below. Not all of the answers will be used. -________________: The type of enzyme regulation process that inhibits the PDH complex. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

Phosphorylation is the process that inhibits the PDH (pyruvate dehydrogenase) complex by adding a phosphate group, thereby regulating its activity.

Question 10

Choose the correct answer from the list below. Not all of the answers will be used. -Where does the citric acid cycle take place in the cell? A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

The citric acid cycle takes place in the mitochondria of the cell, where it plays a central role in the metabolic process of converting carbohydrates, fats, and proteins into carbon dioxide and water to generate a form of usable energy (ATP).

Question 11

Choose the correct answer from the list below. Not all of the answers will be used. -The coenzyme ________________ is the prosthetic group in the decarboxylation of pyruvate. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

Thiamine pyrophosphate is the coenzyme that acts as a prosthetic group in the decarboxylation of pyruvate, a critical step in energy metabolism.

Question 12

Choose the correct answer from the list below. Not all of the answers will be used. -The activated carrier of acyl groups is ________________. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

The answer of Choose the correct answer from the list...

Question 13

__________________ inserts the lipoamide arm of the SH domain deep into the channel in E₁.

Accepted Answer

The answer of __________________ inserts the lipoamide arm of the...

Question 14

__________________ is the critical functional group of lipoamide responsible for carrying acetyl groups and maintaining the free energy of CoA.

Accepted Answer

The answer of __________________ is the critical functional group of...

Question 15

__________________ provides a flexible linkage for substrate to move between active sites on the PDH.

Accepted Answer

The answer of __________________ provides a flexible linkage for substrate...

Question 16

The high-energy charge which results in increasing concentration of NADH __________________ the activity of PDH.

Accepted Answer

The answer of The high-energy charge which results in increasing...

Question 17

Decarboxylation, oxidation, and __________________ are the three steps critical to preserve the free energy derived from decarboxylation of the PDH complex.

Accepted Answer

The answer of Decarboxylation, oxidation, and __________________ are the three...

Question 18

Choose the correct answer from the list below. Not all of the answers will be used. -________________: Arsenite inhibits the function of this component of the PDH. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

The answer of Choose the correct answer from the list...

Question 19

Choose the correct answer from the list below. Not all of the answers will be used. -________________ is a large, multi-subunit enzyme complex that links glycolysis and the citric acid cycle under aerobic conditions. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

Pyruvate dehydrogenase is the enzyme complex that connects glycolysis and the citric acid cycle by converting pyruvate into acetyl CoA in the presence of oxygen.

Question 20

Choose the correct answer from the list below. Not all of the answers will be used. -________________ provides a flexible linker between active siteswithin the pyruvate dehydrogenase (PDH) complex. A)scurvy B)phosphorylation C)beriberi D)mitochondria E)acetyl CoA F)E₃ G)thiamine pyrophosphate H)lipoamide I)pyruvate dehydrogenase J)coenzyme A K)E₁ L)glyoxylate cycle

Accepted Answer

Lipoamide acts as a flexible arm in the pyruvate dehydrogenase complex, allowing the active sites to interact efficiently.

Quiz 18: Preparation for the Cycle

Choose the correct answer from the list below. Not all of the answers will be used. -________________: Pyruvate is decarboxylated at this active site in PDH.

A deficiency in the vitamin thiamine causes the disease ____________.

PDH is inactivated when it the enzyme is __________________.

Choose the correct answer from the list below. Not all of the answers will be used. -In the presence of oxygen, pyruvate is converted to ________________.

E1 of the PDH complex requires the coenzyme __________________ for proper activity.

Choose the correct answer from the list below. Not all of the answers will be used. -________________ is caused by a deficiency in vitamin B1.

E2 of the PDH complex contains a lipoyl group that is covalently attached to a __________________ residue of the enzyme.

__________________ is the PDH subunit responsible for the regeneration of the oxidized form of lipoamide.

Choose the correct answer from the list below. Not all of the answers will be used. -________________: The type of enzyme regulation process that inhibits the PDH complex.

Choose the correct answer from the list below. Not all of the answers will be used. -Where does the citric acid cycle take place in the cell?

Choose the correct answer from the list below. Not all of the answers will be used. -The coenzyme ________________ is the prosthetic group in the decarboxylation of pyruvate.

Choose the correct answer from the list below. Not all of the answers will be used. -The activated carrier of acyl groups is ________________.

__________________ inserts the lipoamide arm of the SH domain deep into the channel in E1.