BIO 110 EXAM 2 QUESTIONS AND ANSWERS | COMPLETE INTRODUCTORY
BIOLOGY EXAM 2 STUDY GUIDE 2026/2027
Reactants capable of interacting to form products in a chemical reaction must first overcome a
thermodynamic barrier known as the reaction's - ANS ✔✔Activation Energy
Which of the following statements regarding enzymes is true? - ANS ✔✔Enzymes increase the rate of a
reaction by lowering the activation energy barrier
The active site of an enzyme is the region that - ANS ✔✔Is involved in the catalytic reaction of the
enzyme
Increasing the substrate concentration in an enzymatic reaction could overcome which of the following?
- ANS ✔✔Competitive Inhibition
The mechanism in which the end product of a metabolic pathway inhibits an earlier step in the pathway
is most precisely described as - ANS ✔✔Feedback Inhibition
How does an enzyme increase the rate of the chemical reaction it catalyzes? - ANS ✔✔An enzyme
reduces the free energy of activation of the reaction it catalyzes
Which statement about the binding of enzymes and substrates is correct? - ANS ✔✔When substrate
molecules bind to the active site of the enzyme, the enzyme undergoes a slight change in shape
According to the induced fit hypothesis of enzyme catalysis, which of the following is correct? - ANS
✔✔The binding of the substrate changes the shape of the enzyme's active site
Besides turning enzymes on or off, what other means does a cell use to control enzymatic activity? - ANS
✔✔Localization of enzymes into specific organelles or membranes
A series of enzymes catalyze the reaction X → Y → Z → A. Product A binds to the enzyme that converts X
to Y at a position remote from its active site. This binding decreases the activity of the enzyme.
What is substance X? - ANS ✔✔A substrate
What is the term for metabolic pathways that release stored energy by breaking down complex
molecules? - ANS ✔✔Catabolic pathways
When electrons move closer to a more electronegative atom, what happens? - ANS ✔✔The more
electronegative atom is reduced, and energy is released
When a molecule of NAD+ (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a proton),
the molecule becomes - ANS ✔✔Reduced
, Which of the following statements describes NAD+? - ANS ✔✔NAD+ is reduced to NADH during
glycolysis, pyruvate oxidation, and the citric acid cycle
The ATP made during glycolysis is generated by - ANS ✔✔Substrate-level phosphorylation
The oxygen consumed during cellular respiration is involved directly in which process or event? - ANS
✔✔Accepting electrons at the end of the electron transport chain
How many NADH are produced by glycolysis? - ANS ✔✔2
In glycolysis, ATP molecules are produced by ___________. - ANS ✔✔Substrate-level phosphorylation
Which of these is NOT a product of glycolysis? - ANS ✔✔FADH2
In glycolysis, what starts the process of glucose oxidation? - ANS ✔✔ATP
In glycolysis there is a net gain of ______ ATP. - ANS ✔✔2
Which process in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent? - ANS
✔✔Glycolysis
Starting with one molecule of glucose, the energy-containing products of glycolysis are - ANS ✔✔2
NADH, 2 pyruvate, and 2 ATP
Why is glycolysis described as having an investment phase and a payoff phase? - ANS ✔✔It uses stored
ATP and then forms a net increase in ATP
Which of these enters the citric acid cycle? - ANS ✔✔Acetyl CoA
In the citric acid cycle, ATP molecules are produced by _________. - ANS ✔✔Substrate-level
phosphorylation
Which of these is NOT a product of the citric acid cycle? - ANS ✔✔Acetyl CoA
What happened to most of the energy that the cell obtains from the oxidation of glucose? - ANS ✔✔It is
stored in NADH and FADH2
Where are the proteins of the electron transport chain located? - ANS ✔✔Mitochondrial intermembrane
space
In cellular respiration, the energy for most ATP synthesis is supplied by - ANS ✔✔A proton gradient
across a membrane
The primary role of oxygen in cellular respiration is to - ANS ✔✔Act as an acceptor for electrons and
hydrogen, forming water
Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic
cells? - ANS ✔✔Mitochondrial intermembrane space
BIOLOGY EXAM 2 STUDY GUIDE 2026/2027
Reactants capable of interacting to form products in a chemical reaction must first overcome a
thermodynamic barrier known as the reaction's - ANS ✔✔Activation Energy
Which of the following statements regarding enzymes is true? - ANS ✔✔Enzymes increase the rate of a
reaction by lowering the activation energy barrier
The active site of an enzyme is the region that - ANS ✔✔Is involved in the catalytic reaction of the
enzyme
Increasing the substrate concentration in an enzymatic reaction could overcome which of the following?
- ANS ✔✔Competitive Inhibition
The mechanism in which the end product of a metabolic pathway inhibits an earlier step in the pathway
is most precisely described as - ANS ✔✔Feedback Inhibition
How does an enzyme increase the rate of the chemical reaction it catalyzes? - ANS ✔✔An enzyme
reduces the free energy of activation of the reaction it catalyzes
Which statement about the binding of enzymes and substrates is correct? - ANS ✔✔When substrate
molecules bind to the active site of the enzyme, the enzyme undergoes a slight change in shape
According to the induced fit hypothesis of enzyme catalysis, which of the following is correct? - ANS
✔✔The binding of the substrate changes the shape of the enzyme's active site
Besides turning enzymes on or off, what other means does a cell use to control enzymatic activity? - ANS
✔✔Localization of enzymes into specific organelles or membranes
A series of enzymes catalyze the reaction X → Y → Z → A. Product A binds to the enzyme that converts X
to Y at a position remote from its active site. This binding decreases the activity of the enzyme.
What is substance X? - ANS ✔✔A substrate
What is the term for metabolic pathways that release stored energy by breaking down complex
molecules? - ANS ✔✔Catabolic pathways
When electrons move closer to a more electronegative atom, what happens? - ANS ✔✔The more
electronegative atom is reduced, and energy is released
When a molecule of NAD+ (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a proton),
the molecule becomes - ANS ✔✔Reduced
, Which of the following statements describes NAD+? - ANS ✔✔NAD+ is reduced to NADH during
glycolysis, pyruvate oxidation, and the citric acid cycle
The ATP made during glycolysis is generated by - ANS ✔✔Substrate-level phosphorylation
The oxygen consumed during cellular respiration is involved directly in which process or event? - ANS
✔✔Accepting electrons at the end of the electron transport chain
How many NADH are produced by glycolysis? - ANS ✔✔2
In glycolysis, ATP molecules are produced by ___________. - ANS ✔✔Substrate-level phosphorylation
Which of these is NOT a product of glycolysis? - ANS ✔✔FADH2
In glycolysis, what starts the process of glucose oxidation? - ANS ✔✔ATP
In glycolysis there is a net gain of ______ ATP. - ANS ✔✔2
Which process in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent? - ANS
✔✔Glycolysis
Starting with one molecule of glucose, the energy-containing products of glycolysis are - ANS ✔✔2
NADH, 2 pyruvate, and 2 ATP
Why is glycolysis described as having an investment phase and a payoff phase? - ANS ✔✔It uses stored
ATP and then forms a net increase in ATP
Which of these enters the citric acid cycle? - ANS ✔✔Acetyl CoA
In the citric acid cycle, ATP molecules are produced by _________. - ANS ✔✔Substrate-level
phosphorylation
Which of these is NOT a product of the citric acid cycle? - ANS ✔✔Acetyl CoA
What happened to most of the energy that the cell obtains from the oxidation of glucose? - ANS ✔✔It is
stored in NADH and FADH2
Where are the proteins of the electron transport chain located? - ANS ✔✔Mitochondrial intermembrane
space
In cellular respiration, the energy for most ATP synthesis is supplied by - ANS ✔✔A proton gradient
across a membrane
The primary role of oxygen in cellular respiration is to - ANS ✔✔Act as an acceptor for electrons and
hydrogen, forming water
Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic
cells? - ANS ✔✔Mitochondrial intermembrane space
