BIOD 171 Module 2 Exam ( 3 Versions, Latest-2025/2026): CORRECT AND VERIFIED
ANSWERS |100 % Correct|
What is cellular metabolism? -CORRECT ANSWER-Metabolism is a controlled set of
biochemical reactions that occur in living organisms in order to maintain life
What is the primary function of enzymes, and how are they regulated? -CORRECT ANSWER-
Enzymes speed up chemical reactions. Most notably, the enzyme is not consumed during the
reaction and can be used repeatedly by the cell. Enzymes can also be regulated by a cofactor
such that in the absence of the proper cofactor, enzymes are inactive while in its presence
enzymes are active.
What is the difference between catabolism and anabolism? -CORRECT ANSWER-Catabolism
is the process of breaking down larger molecules into useful energy sources whereas
anabolism is the building up or biosynthesis od macromolecules from smaller molecular
units into larger complexes, most often associated with cellular growth and repair
ATP has the energy to ______, while ADP has the capacity to ______ energy. -CORRECT
ANSWER-Donate, accept
Chemotrophs can be subdivided into what two additional subgroups? -CORRECT ANSWER-
Chemotrophs, which acquire energy from preformed chemicals found in the environment,
can be divided into either organotrophs (removing electrons from organic molecules such as
glucose) or lithotrophs, which remove electrons from inorganic molecules
Chemotrophs utilize which form of phosphorylation? -CORRECT ANSWER-Chemotrophs use
oxidative phosphorylation (may also accept substrate level phosphorylation). Oxidative
phosphorylation utilizes the energy released by the chemical oxidation of nutrients to
reform ATP
,What are the three distinct stages in the catabolism of glucose? -CORRECT ANSWER-
Glycolysis is the first step of this process and yields 2 molecules of ATP. Next, by either
fermentation (or respiration) 2 additional molecules of ATP can be produces. Last, the
electron transport chain (ETC) produces 34 ATP via an oxidative phosphorylation event at the
plasma membrane.
What are the reactants of glycolysis? -CORRECT ANSWER-Reactants are defined as any
molecules present and involved at the beginning of a specific chemical reaction (ie)
glycolysis. In terms of writing out a chemical reaction, the reactants are everything located
to the left of the arrow. The reactants of glycolysis are glucose, the co-enzyme NAD+ and
ATP.
How are the TCA and ETC related? -CORRECT ANSWER-The end products of the Kreb's (TCA)
cycle are used to fuel the electron transport chain. In other words, as the Kreb's cycle (TCA)
produces an abundance of reduced electron carriers (NADH and FADH2), it fuels the ETC. As
the electrons are transferred from NADH/FADH2 to terminal electron acceptors a proton
motor force is generated, ATP synthase is activated and up to 34 molecules of ATP can be
produced.
In the absence of sugars, are entirely different metabolic pathways used to process
alternative sugar sources (fructose or lactose)? -CORRECT ANSWER-No. Additional enzymatic
steps are simply required at the beginning of catabolism to convert complex sugars into
usable forms of either glucose or a glucose intermediate (glucose-6-phosphate)
Proteases are used to catabolize what? -CORRECT ANSWER-Proteases are used to
breakdown proteins (whereas lipases are used to breakdown lipids)
Excluding sugars, what are the other sources of energy? Which is highest in energy? -
CORRECT ANSWER-Carbohydrates, proteins, and lipids can all serve as potential energy
sources in the absence of sugar. Lipids are rich in energy, often having several reduced
carbon molecules (high in hydrogen content) that can be used in both the TCA and ETC
cycles
In what organelle does photosynthesis take place? -CORRECT ANSWER-Photosynthesis, the
process of capturing sunlight and converting it into a usable energy source, occurs in the
, chloroplasts. Chloroplasts are double-membrane enclosed organelles. Each chloroplast
contains the green photosynthetic pigment chlorophyll.
What are the two main strategies for replenishing cellular concentrations of NAD+, and
when are these strategies utilized? -CORRECT ANSWER-Fermentation and respiration are the
two strategies used by the cell to convert NADH (end product of glycolysis) back to NAD+.
Fermentation occurs in the absence of oxygen (anaerobic conditions) while respiration
occurs under aerobic (presence of oxygen) conditions. Notably, respiration is more efficient
than fermentation.
In phosphorylation, the light reactions always occur where? -CORRECT ANSWER-The process
of converting light energy into chemical energy (photophosphorylation) always occurs in the
membrane. Similar to the electron transport chain, one of its main functions is to generate a
proton concentration gradient to generate ATP.
What are the byproducts of light reactions used for in dark reactions? -CORRECT ANSWER-
The ATP and NADPH produced via light reactions are used in dark reactions to convert
carbon dioxide and water into organic carbon compounds as well as useful carbohydrates (a
process called carbon fixation)
What is the chemical reaction for the Calvin cycle? -CORRECT ANSWER-6 CO2 + 18 ATP + 12
NADPH + 12 H2O --> C6H12O6 + 18 ADP + 12 NADP+
What determines the specificity of an enzyme? -CORRECT ANSWER-The specificity of an
enzyme is heavily influenced by its active site - a unique chemical structure bound only by
select target molecules. The structure is influenced by the amino acid composition of the
protein as this in turn influences the fold, shape, and 'appearance' of the enzyme. The active
site (and its target protein) can be thought of as a lock-and-key relationship. The active site
provides specificity (like a lock) that only specific target proteins can bind - much like how
only a specific key will fit into, unlock, and 'activate' a lock
Do catabolic reactions release or consume energy? -CORRECT ANSWER-Release
Do anabolic pathways release or consume energy? -CORRECT ANSWER-Consume
ANSWERS |100 % Correct|
What is cellular metabolism? -CORRECT ANSWER-Metabolism is a controlled set of
biochemical reactions that occur in living organisms in order to maintain life
What is the primary function of enzymes, and how are they regulated? -CORRECT ANSWER-
Enzymes speed up chemical reactions. Most notably, the enzyme is not consumed during the
reaction and can be used repeatedly by the cell. Enzymes can also be regulated by a cofactor
such that in the absence of the proper cofactor, enzymes are inactive while in its presence
enzymes are active.
What is the difference between catabolism and anabolism? -CORRECT ANSWER-Catabolism
is the process of breaking down larger molecules into useful energy sources whereas
anabolism is the building up or biosynthesis od macromolecules from smaller molecular
units into larger complexes, most often associated with cellular growth and repair
ATP has the energy to ______, while ADP has the capacity to ______ energy. -CORRECT
ANSWER-Donate, accept
Chemotrophs can be subdivided into what two additional subgroups? -CORRECT ANSWER-
Chemotrophs, which acquire energy from preformed chemicals found in the environment,
can be divided into either organotrophs (removing electrons from organic molecules such as
glucose) or lithotrophs, which remove electrons from inorganic molecules
Chemotrophs utilize which form of phosphorylation? -CORRECT ANSWER-Chemotrophs use
oxidative phosphorylation (may also accept substrate level phosphorylation). Oxidative
phosphorylation utilizes the energy released by the chemical oxidation of nutrients to
reform ATP
,What are the three distinct stages in the catabolism of glucose? -CORRECT ANSWER-
Glycolysis is the first step of this process and yields 2 molecules of ATP. Next, by either
fermentation (or respiration) 2 additional molecules of ATP can be produces. Last, the
electron transport chain (ETC) produces 34 ATP via an oxidative phosphorylation event at the
plasma membrane.
What are the reactants of glycolysis? -CORRECT ANSWER-Reactants are defined as any
molecules present and involved at the beginning of a specific chemical reaction (ie)
glycolysis. In terms of writing out a chemical reaction, the reactants are everything located
to the left of the arrow. The reactants of glycolysis are glucose, the co-enzyme NAD+ and
ATP.
How are the TCA and ETC related? -CORRECT ANSWER-The end products of the Kreb's (TCA)
cycle are used to fuel the electron transport chain. In other words, as the Kreb's cycle (TCA)
produces an abundance of reduced electron carriers (NADH and FADH2), it fuels the ETC. As
the electrons are transferred from NADH/FADH2 to terminal electron acceptors a proton
motor force is generated, ATP synthase is activated and up to 34 molecules of ATP can be
produced.
In the absence of sugars, are entirely different metabolic pathways used to process
alternative sugar sources (fructose or lactose)? -CORRECT ANSWER-No. Additional enzymatic
steps are simply required at the beginning of catabolism to convert complex sugars into
usable forms of either glucose or a glucose intermediate (glucose-6-phosphate)
Proteases are used to catabolize what? -CORRECT ANSWER-Proteases are used to
breakdown proteins (whereas lipases are used to breakdown lipids)
Excluding sugars, what are the other sources of energy? Which is highest in energy? -
CORRECT ANSWER-Carbohydrates, proteins, and lipids can all serve as potential energy
sources in the absence of sugar. Lipids are rich in energy, often having several reduced
carbon molecules (high in hydrogen content) that can be used in both the TCA and ETC
cycles
In what organelle does photosynthesis take place? -CORRECT ANSWER-Photosynthesis, the
process of capturing sunlight and converting it into a usable energy source, occurs in the
, chloroplasts. Chloroplasts are double-membrane enclosed organelles. Each chloroplast
contains the green photosynthetic pigment chlorophyll.
What are the two main strategies for replenishing cellular concentrations of NAD+, and
when are these strategies utilized? -CORRECT ANSWER-Fermentation and respiration are the
two strategies used by the cell to convert NADH (end product of glycolysis) back to NAD+.
Fermentation occurs in the absence of oxygen (anaerobic conditions) while respiration
occurs under aerobic (presence of oxygen) conditions. Notably, respiration is more efficient
than fermentation.
In phosphorylation, the light reactions always occur where? -CORRECT ANSWER-The process
of converting light energy into chemical energy (photophosphorylation) always occurs in the
membrane. Similar to the electron transport chain, one of its main functions is to generate a
proton concentration gradient to generate ATP.
What are the byproducts of light reactions used for in dark reactions? -CORRECT ANSWER-
The ATP and NADPH produced via light reactions are used in dark reactions to convert
carbon dioxide and water into organic carbon compounds as well as useful carbohydrates (a
process called carbon fixation)
What is the chemical reaction for the Calvin cycle? -CORRECT ANSWER-6 CO2 + 18 ATP + 12
NADPH + 12 H2O --> C6H12O6 + 18 ADP + 12 NADP+
What determines the specificity of an enzyme? -CORRECT ANSWER-The specificity of an
enzyme is heavily influenced by its active site - a unique chemical structure bound only by
select target molecules. The structure is influenced by the amino acid composition of the
protein as this in turn influences the fold, shape, and 'appearance' of the enzyme. The active
site (and its target protein) can be thought of as a lock-and-key relationship. The active site
provides specificity (like a lock) that only specific target proteins can bind - much like how
only a specific key will fit into, unlock, and 'activate' a lock
Do catabolic reactions release or consume energy? -CORRECT ANSWER-Release
Do anabolic pathways release or consume energy? -CORRECT ANSWER-Consume
