BISC 261 Exam 2024 with Questions with
100% Correct Answers
__________ is a measure of the randomness or disorder of a system. - Answer Entropy
Which of the following is not true about enzymes? - Answer A. Enzymes are
catalysts that speed up reactions.
B. Enzymes are proteins that can be denatured by changes in pH or temperature.
C. Enzymes are highly specific for the substrates they react with and catalyze only one
or a limited set of possible reactions with those substrates.
D. NONE of the choices****
(T/F) Each enzyme normally has specific pH and temperature optima at which
they function best - Answer TRUE
(T/F) The Michaelis constant (Km) of an enzyme is the substrate concentration
that produces maximum velocity. - Answer FALSE
(T/F) Enzyme activity can be greatly affected by the pH and the temperature of
the environment in which the enzyme must function. - Answer TRUE
(T/F) When the amount of enzyme present is held constant, the rate of a reaction will
continue to increase as long as the substrate concentration increases. - Answer FALSE
,(T/F) Enzymes increase the rate of a reaction but do not alter equilibrium constants -
Answer TRUE
(T/F) Enzymes increase the rate of a reaction by increasing molecular motion,
thereby providing kinetic energy to drive the reaction. - Answer FALSE
Enzymes are usually named based on - Answer the substrates they act on and the type
of reaction they catalyze.
The most specific term usually used to describe a substance in a biological system
that increases the rate of a reaction without being permanently changed by the
reaction is a(n) - Answer enzyme
The substrate of an enzyme binds at the - Answer active site
A complete enzyme that consists of a protein component and a nonprotein
component is called a(n) - Answer holoenzyme
A nonprotein component of an enzyme that is loosely attached to the
protein component is referred to as a(n) - Answer coenzyme.
The nonprotein component of an enzyme that is firmly attached to the protein is
called a(n) - Answer prosthetic group
If an enzyme consists of a protein component and a non-protein component, the
protein component is referred as the - Answer apoenzyme
, If all available enzyme molecules are binding substrate and converting it to produce
as rapidly as possible, the reaction is said to be proceeding at __________ velocity. -
Answer maximal
A(n) _______________ increases the rate of a reaction without being permanently
altered by the reaction. - Answer catalyst
Enzymes function as catalysts by - Answer bringing the substrates together at the
active site, in effect concentrating them and bringing the substrates together at the
active site correctly oriented for the reaction.
Enzymes catalyze a reaction by - Answer decreasing the activation energy of
the reaction.
The energy required to bring the substrates of a reaction together in the correct way
to reach the transition state is called - Answer activation energy.
(T/F) One important ribozyme located in mitochondria is responsible for
catalyzing peptide bond formation during protein synthesis. - Answer FALSE
Which of the following is a reason for metabolic regulation? - Answer A. Maintain cell
components at appropriate levels.
B. Conserve materials.
C. Ensure efficient use energy stores.
D. All of the choices.*****
In metabolic channeling, the regulation of metabolic pathways is controlled by the
__________ of metabolites and enzymes involved in the pathway. - Answer location
100% Correct Answers
__________ is a measure of the randomness or disorder of a system. - Answer Entropy
Which of the following is not true about enzymes? - Answer A. Enzymes are
catalysts that speed up reactions.
B. Enzymes are proteins that can be denatured by changes in pH or temperature.
C. Enzymes are highly specific for the substrates they react with and catalyze only one
or a limited set of possible reactions with those substrates.
D. NONE of the choices****
(T/F) Each enzyme normally has specific pH and temperature optima at which
they function best - Answer TRUE
(T/F) The Michaelis constant (Km) of an enzyme is the substrate concentration
that produces maximum velocity. - Answer FALSE
(T/F) Enzyme activity can be greatly affected by the pH and the temperature of
the environment in which the enzyme must function. - Answer TRUE
(T/F) When the amount of enzyme present is held constant, the rate of a reaction will
continue to increase as long as the substrate concentration increases. - Answer FALSE
,(T/F) Enzymes increase the rate of a reaction but do not alter equilibrium constants -
Answer TRUE
(T/F) Enzymes increase the rate of a reaction by increasing molecular motion,
thereby providing kinetic energy to drive the reaction. - Answer FALSE
Enzymes are usually named based on - Answer the substrates they act on and the type
of reaction they catalyze.
The most specific term usually used to describe a substance in a biological system
that increases the rate of a reaction without being permanently changed by the
reaction is a(n) - Answer enzyme
The substrate of an enzyme binds at the - Answer active site
A complete enzyme that consists of a protein component and a nonprotein
component is called a(n) - Answer holoenzyme
A nonprotein component of an enzyme that is loosely attached to the
protein component is referred to as a(n) - Answer coenzyme.
The nonprotein component of an enzyme that is firmly attached to the protein is
called a(n) - Answer prosthetic group
If an enzyme consists of a protein component and a non-protein component, the
protein component is referred as the - Answer apoenzyme
, If all available enzyme molecules are binding substrate and converting it to produce
as rapidly as possible, the reaction is said to be proceeding at __________ velocity. -
Answer maximal
A(n) _______________ increases the rate of a reaction without being permanently
altered by the reaction. - Answer catalyst
Enzymes function as catalysts by - Answer bringing the substrates together at the
active site, in effect concentrating them and bringing the substrates together at the
active site correctly oriented for the reaction.
Enzymes catalyze a reaction by - Answer decreasing the activation energy of
the reaction.
The energy required to bring the substrates of a reaction together in the correct way
to reach the transition state is called - Answer activation energy.
(T/F) One important ribozyme located in mitochondria is responsible for
catalyzing peptide bond formation during protein synthesis. - Answer FALSE
Which of the following is a reason for metabolic regulation? - Answer A. Maintain cell
components at appropriate levels.
B. Conserve materials.
C. Ensure efficient use energy stores.
D. All of the choices.*****
In metabolic channeling, the regulation of metabolic pathways is controlled by the
__________ of metabolites and enzymes involved in the pathway. - Answer location
