NAS EXAM #2 QUESTIONS WITH
ANSWERS
Why is chemical energy required by cells? - The answer is to maintain homeostasis
Define cell respiration as the mechanism for extracting energy from fuel molecules,
namely the oxidation of glucose to make ATP.
What is the function of decreased coenzymes? - ANSWER: They transfer energy to
another chemical.
Explain the role of oxidation-reduction reactions in the creation of ATP. -
ANSWER A reaction that delivers energy to reduced coenzymes for ATP
production.
How can hydrogen atoms get involved in redox reactions? - ANSWER Redox
reactions normally result in the loss of hydrogen atoms.
What happens to the energy contained in the freshly created reduced coenzyme?
Why is this known as phosphorylation? - ANSWER: Phosphorylation is the
insertion of a phosphate group to a molecule.
Name the four processes of cell respiration - ANSWER 1. Glycolysis: 2. Acetyl
coenzyme A is formed (3). Krebs cycle, stage 4. Electron Transport Chain
Glycolysis is "anaerobic" while the other three routes are "aerobic." - ANSWER
Because oxygen is not required to make ATP during glycolysis.
Where does glycolysis occur? - Answer in the cytoplasm.
,Two ATP molecules are required to divide a glucose molecule. However,
glycolysis is the process by which ATP is produced. How much ATP is produced
throughout this procedure, and what is the net gain? - ANSWER: 4 ATP gross (2
net)
How many reduced coenzyme molecules are created during glycolysis? -
ANSWER 2.
Glycolysis produces two molecules. Identify them. - ANSWER: Pyruvic acid and
NADH + H+
Describe the conditions that result in lactic acid generation. ANSWER: anaerobic,
insufficient oxygen.
Further oxidation of pyruvic acid molecules occurs in the matrix of the
mitochondria.
Describe the two stages involved in the production of acetyl Co-enzyme A. -
ANSWER 1. Decarboxylation removes a molecule of CO2 from the pyruvate.
Pyruvic acid is oxidized. 2. The acetyl group bonds to Co-enzyme A to generate
acetyl CoA.
Each glucose molecule produces six CO2 molecules as waste gas. How many CO2
molecules are created during glycolysis versus the Krebs cycle? - ANSWER 2:
glycolysis, 4: Krebs cycle.
How much ATP is produced throughout the Krebs cycle? - ANSWER 2.
What happens to the remaining energy captured by the Krebs cycle? - ANSWER: It
is transferred to reduced coenzymes, which pass via the ETC and are transformed
to ATP.
, What is the primary function of the Krebs cycle? - ANSWER: The formation of
decreased coenzymes.
What is the role of the electron transport chain? - ANSWER The production of
ATP
What is a byproduct of the ETC reaction? ANSWER Water as the H- is liberated
and mixed with oxygen.
Define chemiosmosis: the process by which ATP is created as hydrogen ions
migrate down a concentration gradient.
Which protein enzyme is involved in chemiosmosis? - Answer: ATP Synthase.
Why is ATP production an example of an anabolic reaction? - ANSWER ATP is
formed by combining simpler molecules into more complex molecules.
Catabolism is defined as the breakdown of larger, more complex food molecules in
order to extract energy from them.
Recognize the two distinct types of reactions involved in energy transfer. -
ANSWER 1. Oxidation and reduction reactions yield reduced coenzymes that
absorb energy from high-energy fuel molecules. 2. ATP production processes
create ATP, which stores the energy derived from reduced coenzymes.
Describe an oxidation reaction and provide an example of this energy transfer
process - ANSWER Oxidation releases energy in the form of hydrogen atoms from
high-energy fuel molecules. One example is the conversion of lactic acid to pyruvic
acid.
ANSWERS
Why is chemical energy required by cells? - The answer is to maintain homeostasis
Define cell respiration as the mechanism for extracting energy from fuel molecules,
namely the oxidation of glucose to make ATP.
What is the function of decreased coenzymes? - ANSWER: They transfer energy to
another chemical.
Explain the role of oxidation-reduction reactions in the creation of ATP. -
ANSWER A reaction that delivers energy to reduced coenzymes for ATP
production.
How can hydrogen atoms get involved in redox reactions? - ANSWER Redox
reactions normally result in the loss of hydrogen atoms.
What happens to the energy contained in the freshly created reduced coenzyme?
Why is this known as phosphorylation? - ANSWER: Phosphorylation is the
insertion of a phosphate group to a molecule.
Name the four processes of cell respiration - ANSWER 1. Glycolysis: 2. Acetyl
coenzyme A is formed (3). Krebs cycle, stage 4. Electron Transport Chain
Glycolysis is "anaerobic" while the other three routes are "aerobic." - ANSWER
Because oxygen is not required to make ATP during glycolysis.
Where does glycolysis occur? - Answer in the cytoplasm.
,Two ATP molecules are required to divide a glucose molecule. However,
glycolysis is the process by which ATP is produced. How much ATP is produced
throughout this procedure, and what is the net gain? - ANSWER: 4 ATP gross (2
net)
How many reduced coenzyme molecules are created during glycolysis? -
ANSWER 2.
Glycolysis produces two molecules. Identify them. - ANSWER: Pyruvic acid and
NADH + H+
Describe the conditions that result in lactic acid generation. ANSWER: anaerobic,
insufficient oxygen.
Further oxidation of pyruvic acid molecules occurs in the matrix of the
mitochondria.
Describe the two stages involved in the production of acetyl Co-enzyme A. -
ANSWER 1. Decarboxylation removes a molecule of CO2 from the pyruvate.
Pyruvic acid is oxidized. 2. The acetyl group bonds to Co-enzyme A to generate
acetyl CoA.
Each glucose molecule produces six CO2 molecules as waste gas. How many CO2
molecules are created during glycolysis versus the Krebs cycle? - ANSWER 2:
glycolysis, 4: Krebs cycle.
How much ATP is produced throughout the Krebs cycle? - ANSWER 2.
What happens to the remaining energy captured by the Krebs cycle? - ANSWER: It
is transferred to reduced coenzymes, which pass via the ETC and are transformed
to ATP.
, What is the primary function of the Krebs cycle? - ANSWER: The formation of
decreased coenzymes.
What is the role of the electron transport chain? - ANSWER The production of
ATP
What is a byproduct of the ETC reaction? ANSWER Water as the H- is liberated
and mixed with oxygen.
Define chemiosmosis: the process by which ATP is created as hydrogen ions
migrate down a concentration gradient.
Which protein enzyme is involved in chemiosmosis? - Answer: ATP Synthase.
Why is ATP production an example of an anabolic reaction? - ANSWER ATP is
formed by combining simpler molecules into more complex molecules.
Catabolism is defined as the breakdown of larger, more complex food molecules in
order to extract energy from them.
Recognize the two distinct types of reactions involved in energy transfer. -
ANSWER 1. Oxidation and reduction reactions yield reduced coenzymes that
absorb energy from high-energy fuel molecules. 2. ATP production processes
create ATP, which stores the energy derived from reduced coenzymes.
Describe an oxidation reaction and provide an example of this energy transfer
process - ANSWER Oxidation releases energy in the form of hydrogen atoms from
high-energy fuel molecules. One example is the conversion of lactic acid to pyruvic
acid.
