BCH 361 EXAM 4 CLICKER QUESTIONS WITH
VERIFIED ANSWERS
Why is the conversion of pyruvate to acetyl CoA a decisive step in metabolism in
animals? - Answers - Animals cannot convert acetyl CoA back to glucose
Pyruvate dehydrogenase directly connects the following two metabolic pathways: -
Answers - glycolysis and the citric acid cycle
This enzyme occupies the central position in the multi-enzyme pyruvate dehydrogenase
complex: - Answers - dihydrolipoyl transacetylase
The lipoamide swinging arm is attached to this enzyme in the PDH complex: - Answers
- dihydrolipoyl transacetylase
Conversion of dihydrolipoamide to lipoamide occurs at this enzyme in the PDH
complex: - Answers - dihydrolipoyl dehydrogenase
This acetyl group is transferred to lipoamide in this enzyme of the PDH complex: -
Answers - pyruvate dehydrogenase component
With of these compounds is a stoichiometric coenzyme for pyruvate dehydrogenase? -
Answers - CoA
Acetyl CoA is an important molecule in metabolic pathways because: - Answers - it
contains a high energy thioester bond that can be used to drive chemical reactions
Phosphorylation of the pyruvate dehydrogenase complex: - Answers - increases its
catalytic activity
Acetyl CoA interacts with this PDH enzyme to inhibit PDH complex activity: - Answers -
dihydrolipoyl transacetylase
In the first stage of the citric acid cycle, how many carbon atoms are lost as carbon
dioxide for each molecule of citrate? - Answers - 2
By the end of the second stage of the citric acid cycle, succinyl CoA has been converted
into this 4-carbon compound: - Answers - oxaloacetate
Malate dehydrogenase carries out a reaction with G=+29.7 kJ mol. Why does this
reaction occur spontaneously in cellular conditions? - Answers - The oxaloacetate and
NADH reaction products are present at low concentrations, making the overall reaction
free energy negative
VERIFIED ANSWERS
Why is the conversion of pyruvate to acetyl CoA a decisive step in metabolism in
animals? - Answers - Animals cannot convert acetyl CoA back to glucose
Pyruvate dehydrogenase directly connects the following two metabolic pathways: -
Answers - glycolysis and the citric acid cycle
This enzyme occupies the central position in the multi-enzyme pyruvate dehydrogenase
complex: - Answers - dihydrolipoyl transacetylase
The lipoamide swinging arm is attached to this enzyme in the PDH complex: - Answers
- dihydrolipoyl transacetylase
Conversion of dihydrolipoamide to lipoamide occurs at this enzyme in the PDH
complex: - Answers - dihydrolipoyl dehydrogenase
This acetyl group is transferred to lipoamide in this enzyme of the PDH complex: -
Answers - pyruvate dehydrogenase component
With of these compounds is a stoichiometric coenzyme for pyruvate dehydrogenase? -
Answers - CoA
Acetyl CoA is an important molecule in metabolic pathways because: - Answers - it
contains a high energy thioester bond that can be used to drive chemical reactions
Phosphorylation of the pyruvate dehydrogenase complex: - Answers - increases its
catalytic activity
Acetyl CoA interacts with this PDH enzyme to inhibit PDH complex activity: - Answers -
dihydrolipoyl transacetylase
In the first stage of the citric acid cycle, how many carbon atoms are lost as carbon
dioxide for each molecule of citrate? - Answers - 2
By the end of the second stage of the citric acid cycle, succinyl CoA has been converted
into this 4-carbon compound: - Answers - oxaloacetate
Malate dehydrogenase carries out a reaction with G=+29.7 kJ mol. Why does this
reaction occur spontaneously in cellular conditions? - Answers - The oxaloacetate and
NADH reaction products are present at low concentrations, making the overall reaction
free energy negative
