Biochem 301 Exam | Questions with 100% Correct
Answers| Verified-
What is the name applied to metabolic reactions that replenish the citric acid cycle
intermediates that are depleted because they were used for biosynthesis? -
✔✔Anaplerotic reactions
What form are the carbons from carbohydrates in when they enter the citric acid cycle?
- ✔✔Acetyl CoA
What is produced by a substrate-level phosphorylation in the citric cycle? - ✔✔GTP
What state is the free energy at the standard state for MDH in the direction of the citric
acid in? - ✔✔Positive
What type of reactions fill up a cycle with outside carbon compounds? -
✔✔Anaplerotic reactions
What enzyme in the citric acid cycle is also an example of an iron-sulfur protein? -
✔✔Aconitase or succinate dehydrogenase
What organelles in plants and some bacteria where two-carbon acetyl units are
converted into four-carbon units (succinate) for glucose synthesis. energy production.
and biosynthesis? - ✔✔Glyoxysomes
Which intermediate in the oxidation of isocitrate is decarboxylated to form alpha-
ketoglutarate? - ✔✔Oxalosuccinate
,What energy conditions (high or low) is the citric acid cycle inhibited by? - ✔✔High
What is the first intermediate to be oxidized in the citric acid cycle? - ✔✔Isocitrate
What cycle are organisms that can convert fat into sugar use? - ✔✔Glyoxylate cycle
What would a mutation in the active site of a succinyl CoA synthetase where His is
converted to a lysine would result in? - ✔✔The loss of a succinyl phosphate
intermediate
What molecule initiates the citric acid cycle by reacting with oxaloacetate? -
✔✔Acetyl CoA
What enzyme in muscle is used to catalyze a substrate-level phosphorylation? -
✔✔Succinyl CoA synthetase
Where does the direct channeling of proteins from one enzyme to the next happen? -
✔✔Metabolon
What vitamins are precursors to coenzymes that are necessary for the formation of
succinyl CoA from alpha-ketoglutarate? - ✔✔- Thiamine
- Riboflavin
- Niacin
- Lipoic acid
- Pantothenic acid
What is the isomerization of citrate catalyzed by? - ✔✔Aconitase
, What type of reaction is the formation of citrate from acetyl CoA and oxaloacetate? -
✔✔Condensation reaction
What us/are the chemical change(s) involved in the conversion of citrate into isocitrate?
- ✔✔- Dehydration
- Followed by Hydration
Which reaction is ATP directly formed in the citrate acid cycle? - ✔✔Conversion of
succinyl CoA to succinate
In which step of the citric acid cycle is FADH2 formed? - ✔✔The conversion of
succinate to oxaloacetate
Which compound is oxidized by a multienzyme complex that requires 5 different
coenzymes? - ✔✔Alpha-ketoglutarate
What is the structure of alpha-ketoglutarate? - ✔✔-O2C-CH2-CH2-C(double bonded
to O, bonded to CO2-)
What does succinate dehydrogenase deficiency or genetic mutation result in? -
✔✔Cancer through HIF-1
Approximately how many ATP or GTP equivalents are produced during one turn of the
citric acid cycle? - ✔✔10
What enzymes are key regulatory sites in the citric acid cycle? - ✔✔- Pyruvate
dehydrogenase
Answers| Verified-
What is the name applied to metabolic reactions that replenish the citric acid cycle
intermediates that are depleted because they were used for biosynthesis? -
✔✔Anaplerotic reactions
What form are the carbons from carbohydrates in when they enter the citric acid cycle?
- ✔✔Acetyl CoA
What is produced by a substrate-level phosphorylation in the citric cycle? - ✔✔GTP
What state is the free energy at the standard state for MDH in the direction of the citric
acid in? - ✔✔Positive
What type of reactions fill up a cycle with outside carbon compounds? -
✔✔Anaplerotic reactions
What enzyme in the citric acid cycle is also an example of an iron-sulfur protein? -
✔✔Aconitase or succinate dehydrogenase
What organelles in plants and some bacteria where two-carbon acetyl units are
converted into four-carbon units (succinate) for glucose synthesis. energy production.
and biosynthesis? - ✔✔Glyoxysomes
Which intermediate in the oxidation of isocitrate is decarboxylated to form alpha-
ketoglutarate? - ✔✔Oxalosuccinate
,What energy conditions (high or low) is the citric acid cycle inhibited by? - ✔✔High
What is the first intermediate to be oxidized in the citric acid cycle? - ✔✔Isocitrate
What cycle are organisms that can convert fat into sugar use? - ✔✔Glyoxylate cycle
What would a mutation in the active site of a succinyl CoA synthetase where His is
converted to a lysine would result in? - ✔✔The loss of a succinyl phosphate
intermediate
What molecule initiates the citric acid cycle by reacting with oxaloacetate? -
✔✔Acetyl CoA
What enzyme in muscle is used to catalyze a substrate-level phosphorylation? -
✔✔Succinyl CoA synthetase
Where does the direct channeling of proteins from one enzyme to the next happen? -
✔✔Metabolon
What vitamins are precursors to coenzymes that are necessary for the formation of
succinyl CoA from alpha-ketoglutarate? - ✔✔- Thiamine
- Riboflavin
- Niacin
- Lipoic acid
- Pantothenic acid
What is the isomerization of citrate catalyzed by? - ✔✔Aconitase
, What type of reaction is the formation of citrate from acetyl CoA and oxaloacetate? -
✔✔Condensation reaction
What us/are the chemical change(s) involved in the conversion of citrate into isocitrate?
- ✔✔- Dehydration
- Followed by Hydration
Which reaction is ATP directly formed in the citrate acid cycle? - ✔✔Conversion of
succinyl CoA to succinate
In which step of the citric acid cycle is FADH2 formed? - ✔✔The conversion of
succinate to oxaloacetate
Which compound is oxidized by a multienzyme complex that requires 5 different
coenzymes? - ✔✔Alpha-ketoglutarate
What is the structure of alpha-ketoglutarate? - ✔✔-O2C-CH2-CH2-C(double bonded
to O, bonded to CO2-)
What does succinate dehydrogenase deficiency or genetic mutation result in? -
✔✔Cancer through HIF-1
Approximately how many ATP or GTP equivalents are produced during one turn of the
citric acid cycle? - ✔✔10
What enzymes are key regulatory sites in the citric acid cycle? - ✔✔- Pyruvate
dehydrogenase
