BIOL 230 Exam 2 NEWEST 2025 ACTUAL
EXAM COMPLETE QUESTIONS AND
CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY
GRADED A+||BRAND NEW!!
Which of the following most accurately describes enzyme-substrate interactions?
a. They are stabilized by non-covalent bonds and the enzyme and substrate molecules
change conformation during interaction.
b. They are stabilized by covalent bonds and the enzyme and substrate molecules
change conformation during interaction.
c. They are stabilized by non-covalent bonds and only the substrate molecules change
conformation during interaction.
d. They are stabilized by covalent bonds and only the substrate molecules change
conformation during interaction. - Answer - ✔✔ a
Which of the following are ways by which enzymes facilitate reactions?
a. changing the local charge within the active site
b. mechanical stress on substrate molecules
c. alteration of primary structure of the enzyme
d. A and B - Answer - ✔✔ d
A given reaction A + B <--> C + D has a Keq of 100. If [A] = 10 mM, [B] = 50 mM, [C] =
1 M, and [D] = 5 mM, what is Q and in what direction will the reaction proceed?
a. Q = 10, and the reaction will provide in the forward direction, A + B --> C + D
b. Q = 10, and the reaction will proceed in the reverse direction C + D --> A + B
c. Q = -10, and the reaction will proceed in the reverse direction, C + D --> A + B
d. Q = 0.1, and the reaction will proceed in the reverse direction, C + D --> A + B -
Answer - ✔✔ a (Q = [C][D] / [A][B])
How is the third step of glycolysis, fructose-6-phosphate + Pi --> fructose 1,6-
biphosphate, made energetically favorable?
a. It is made favorable by coupling it with ATP hydrolysis.
b. It is made favorable by coupling it with ATP synthesis.
c. It is energetically favorable by itself with typical biological concentrations.
d. None of the above. - Answer - ✔✔ a
, Which macromolecules produce more ATP per unit mass and why?
a. proteins produce the most ATP because the amino acid cycle produces large number
of acetyl CoA, NADH, and FADH2 molecules for each fatty acid chain
b. fatty acids produce the most ATP because the fatty acid cycle produces large number
of acetyl CoA, NADH, and FADH2 molecules for each fatty acid chain
c. fatty acids produce the most ATP because the fatty acid cycle converts fatty acid
chains to multiple glucose molecules to enter the TCA cycle.
d. carbohydrates produce the most ATP because it includes glycolysis and the TCA
cycle and electron transportation - Answer - ✔✔ b
You have isolated mitochondria from a patient suffering from exhaustion and fatigue.
Measurement of NADH production showed that for each pyruvate in, only 2/5 of the
typical amount of NADH was produced. In addition, there was an excess of alpha-
ketoglutarate. What is the most likely cause of this?
a. There is excess isocitrate.
b. There is excess FADH2.
c. There is a mutation in alpha ketoglutarate dehydrogenase.
d. There is a mutation in isocitrate dehydrogenase. - Answer - ✔✔ c
How is the reaction of malate + NAD+ --> oxaloacetate + NADH + H+, which typically
has a ∆G of +7.1 kcal / mol, made energetically favorable in the TCA cycle?
a. It is coupled with the reaction oxaloacetate + acetyl CoA --> citrate + CoA.
b. it is coupled with the reaction ATP hydrolysis.
c. It is coupled with the reaction NADH + H+ --> NAD+.
d. The concentrations within the mitochondrial matrix make it energetically favorable. -
Answer - ✔✔ a
If one wanted to design an enzyme that rapidly increases reaction velocity over a small
[S] range at a relatively low substrate concentration, what characteristic might one use?
a. Negative cooperativity and a low Km.
b. Negative cooperativity and a high Km.
c. Positive cooperativity and a high Km.
d. Positive cooperativity and a low Km. - Answer - ✔✔ d
Which of the following is true about the cellular distribution of molecules for the aerobic
breakdown of glucose?
a. Pyruvate is found in the cytoplasm and in the mitochondrial matrix while alpha-
ketoglutarate is primarily in the inter membrane space.
b. Pyruvate is found in the cytoplasm and in the mitochondrial matrix while alpha-
ketoglutarate is primarily in the matrix.
EXAM COMPLETE QUESTIONS AND
CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY
GRADED A+||BRAND NEW!!
Which of the following most accurately describes enzyme-substrate interactions?
a. They are stabilized by non-covalent bonds and the enzyme and substrate molecules
change conformation during interaction.
b. They are stabilized by covalent bonds and the enzyme and substrate molecules
change conformation during interaction.
c. They are stabilized by non-covalent bonds and only the substrate molecules change
conformation during interaction.
d. They are stabilized by covalent bonds and only the substrate molecules change
conformation during interaction. - Answer - ✔✔ a
Which of the following are ways by which enzymes facilitate reactions?
a. changing the local charge within the active site
b. mechanical stress on substrate molecules
c. alteration of primary structure of the enzyme
d. A and B - Answer - ✔✔ d
A given reaction A + B <--> C + D has a Keq of 100. If [A] = 10 mM, [B] = 50 mM, [C] =
1 M, and [D] = 5 mM, what is Q and in what direction will the reaction proceed?
a. Q = 10, and the reaction will provide in the forward direction, A + B --> C + D
b. Q = 10, and the reaction will proceed in the reverse direction C + D --> A + B
c. Q = -10, and the reaction will proceed in the reverse direction, C + D --> A + B
d. Q = 0.1, and the reaction will proceed in the reverse direction, C + D --> A + B -
Answer - ✔✔ a (Q = [C][D] / [A][B])
How is the third step of glycolysis, fructose-6-phosphate + Pi --> fructose 1,6-
biphosphate, made energetically favorable?
a. It is made favorable by coupling it with ATP hydrolysis.
b. It is made favorable by coupling it with ATP synthesis.
c. It is energetically favorable by itself with typical biological concentrations.
d. None of the above. - Answer - ✔✔ a
, Which macromolecules produce more ATP per unit mass and why?
a. proteins produce the most ATP because the amino acid cycle produces large number
of acetyl CoA, NADH, and FADH2 molecules for each fatty acid chain
b. fatty acids produce the most ATP because the fatty acid cycle produces large number
of acetyl CoA, NADH, and FADH2 molecules for each fatty acid chain
c. fatty acids produce the most ATP because the fatty acid cycle converts fatty acid
chains to multiple glucose molecules to enter the TCA cycle.
d. carbohydrates produce the most ATP because it includes glycolysis and the TCA
cycle and electron transportation - Answer - ✔✔ b
You have isolated mitochondria from a patient suffering from exhaustion and fatigue.
Measurement of NADH production showed that for each pyruvate in, only 2/5 of the
typical amount of NADH was produced. In addition, there was an excess of alpha-
ketoglutarate. What is the most likely cause of this?
a. There is excess isocitrate.
b. There is excess FADH2.
c. There is a mutation in alpha ketoglutarate dehydrogenase.
d. There is a mutation in isocitrate dehydrogenase. - Answer - ✔✔ c
How is the reaction of malate + NAD+ --> oxaloacetate + NADH + H+, which typically
has a ∆G of +7.1 kcal / mol, made energetically favorable in the TCA cycle?
a. It is coupled with the reaction oxaloacetate + acetyl CoA --> citrate + CoA.
b. it is coupled with the reaction ATP hydrolysis.
c. It is coupled with the reaction NADH + H+ --> NAD+.
d. The concentrations within the mitochondrial matrix make it energetically favorable. -
Answer - ✔✔ a
If one wanted to design an enzyme that rapidly increases reaction velocity over a small
[S] range at a relatively low substrate concentration, what characteristic might one use?
a. Negative cooperativity and a low Km.
b. Negative cooperativity and a high Km.
c. Positive cooperativity and a high Km.
d. Positive cooperativity and a low Km. - Answer - ✔✔ d
Which of the following is true about the cellular distribution of molecules for the aerobic
breakdown of glucose?
a. Pyruvate is found in the cytoplasm and in the mitochondrial matrix while alpha-
ketoglutarate is primarily in the inter membrane space.
b. Pyruvate is found in the cytoplasm and in the mitochondrial matrix while alpha-
ketoglutarate is primarily in the matrix.
