Question 1

What is the primary determinant of the function and specificity of an enzyme?

Accepted Answer

A)  the cofactors bound to the enzyme 
B)  the presence or absence of an allosteric regulator 
C)  prosthetic groups 
D)  the enzyme's conformation 
E)  the pH of its environment 
A)  the cofactors bound to the enzyme 
B)  the presence or absence of an allosteric regulator 
C)  prosthetic groups 
D)  the enzyme's conformation 
E)  the pH of its environment D

Question 2

Which statement is a part of the first law of thermodynamics?

Accepted Answer

A)  Energy can be neither created nor destroyed. 
B)  Energy cannot be transformed. 
C)  The entropy of the universe is constant. 
D)  The entropy of the universe is decreasing. 
E)  Potential energy is the energy of motion. 
A)  Energy can be neither created nor destroyed. 
B)  Energy cannot be transformed. 
C)  The entropy of the universe is constant. 
D)  The entropy of the universe is decreasing. 
E)  Potential energy is the energy of motion. A

Question 3

Which example would have a negative change in entropy?

Accepted Answer

A)  water freezing 
B)  fermentation of wine 
C)  expansion of the universe 
D)  a supernova (stellar explosion) 
E)  a frog's life cycle 
A)  water freezing 
B)  fermentation of wine 
C)  expansion of the universe 
D)  a supernova (stellar explosion) 
E)  a frog's life cycle A

Question 4

The free energy of ATP hydrolysis is -31.0 kJ/mol. The free energy of glucose phosphorylation by hexokinase is +14.3 kJ/mol. These two reactions are coupled to allow them to proceed spontaneously. What is the overall free energy associated with this coupled reaction?

Accepted Answer

A)  -45.3 kJ/mol 
B)  -31 kJ/mol 
C)  -16.7 kJ/mol 
D)  16.7 kJ/mol 
E)  45.3 kJ/mol 
A)  -45.3 kJ/mol 
B)  -31 kJ/mol 
C)  -16.7 kJ/mol 
D)  16.7 kJ/mol 
E)  45.3 kJ/mol

Question 5

What is the name of the specific region of an enzyme responsible for catalysis?

Accepted Answer

A)  functional domain 
B)  active site 
C)  binding site 
D)  allosteric site 
E)  reaction domain 
A)  functional domain 
B)  active site 
C)  binding site 
D)  allosteric site 
E)  reaction domain

Question 6

Define metabolism.

Accepted Answer

Metabolism is the total of all of the ch

Question 7

How do cells overcome the energy requirement of endergonic reactions?

Accepted Answer

A)  coupling ATP synthesis with phosphorylation reactions 
B)  coupling endergonic and exergonic reactions 
C)  coupling endothermic and endergonic reactions 
D)  coupling ATP transport with endergonic reactions 
E)  coupling ATP synthesis with endergonic reactions 
A)  coupling ATP synthesis with phosphorylation reactions 
B)  coupling endergonic and exergonic reactions 
C)  coupling endothermic and endergonic reactions 
D)  coupling ATP transport with endergonic reactions 
E)  coupling ATP synthesis with endergonic reactions

Question 8

The removal of a phosphate group during an enzyme-catalyzed reaction takes ____.

Accepted Answer

A)  1012years 
B)  about 10 milliseconds 
C)  about 1021milliseconds 
D)  more time than for an uncatalyzed reaction 
E)  less time at 1000oC than at 100oC 
A)  1012years 
B)  about 10 milliseconds 
C)  about 1021milliseconds 
D)  more time than for an uncatalyzed reaction 
E)  less time at 1000oC than at 100oC

Question 9

Enzymes aid in metabolism by ____.

Accepted Answer

A)  changing the DG of the reaction 
B)  adding additional reactants to the system 
C)  slowing the rate of some reactions and increasing the rate of other reactions 
D)  stabilizing the transition state 
E)  removing unused reactants from the system 
A)  changing the DG of the reaction 
B)  adding additional reactants to the system 
C)  slowing the rate of some reactions and increasing the rate of other reactions 
D)  stabilizing the transition state 
E)  removing unused reactants from the system

Question 10

What is the ultimate source of energy for almost all organisms?

Accepted Answer

A)  catabolism of sugars 
B)  ATP 
C)  catabolism of fats 
D)  the sun 
E)  catabolism of sugars, fats, and proteins 
A)  catabolism of sugars 
B)  ATP 
C)  catabolism of fats 
D)  the sun 
E)  catabolism of sugars, fats, and proteins

Question 11

The rate of catalysis is proportional to the concentration of the enzyme .

Accepted Answer

A) True 
 B)False

Question 12

At equilibrium, the concentrations of the reactants equals that of the products.

Accepted Answer

A) True 
 B)False

Question 13

Which statement is true for exergonic reactions?

Accepted Answer

A)  A net input of energy is necessary for the reaction to proceed. 
B)  The products have less free energy than the reactants. 
C)  The products have more free energy than the reactants. 
D)  The reactants will always be completely converted to products. 
E)  The entropy of the system is reduced. 
A)  A net input of energy is necessary for the reaction to proceed. 
B)  The products have less free energy than the reactants. 
C)  The products have more free energy than the reactants. 
D)  The reactants will always be completely converted to products. 
E)  The entropy of the system is reduced.

Question 14

How does energy coupling allow chemical reactions that are not spontaneous to proceed?

Accepted Answer

A)  The energy from both reactions increases the total free energy. 
B)  The energy from the endergonic reaction is transferred to the substrate to stabilize it. 
C)  The energy from the endergonic reaction is transferred to the enzyme to stabilize the transition state. 
D)  The energy from the exergonic reaction is transferred to the substrate to stabilize it. 
E)  The energy from the exergonic reaction is transferred to the substrate to destabilize it. 
A)  The energy from both reactions increases the total free energy. 
B)  The energy from the endergonic reaction is transferred to the substrate to stabilize it. 
C)  The energy from the endergonic reaction is transferred to the enzyme to stabilize the transition state. 
D)  The energy from the exergonic reaction is transferred to the substrate to stabilize it. 
E)  The energy from the exergonic reaction is transferred to the substrate to destabilize it.

Question 15

You do an experiment in the laboratory and add increasing amounts of substrate to a solution containing an enzyme and a pH buffer. You incubate the container at the optimal temperature for your enzyme. Each time you add more substrate, you measure the rate of the reaction. If you graph the results with substrate concentration on the x-axis and reaction rate on the y-axis, what will you find over time?

Accepted Answer

A)  The rate of the reaction will proceed with a slope of 1 and continue in a linear fashion indefinitely or until you run out of reactants. 
B)  The rate of the reaction will increase rapidly, taper off, and plateau. 
C)  The rate of the reaction will increase slowly, plateau, and then drop sharply back to zero. 
D)  The resulting graph will be a perfect bell curve. 
E)  There is no way to predict what the graph will look like without more information. 
A)  The rate of the reaction will proceed with a slope of 1 and continue in a linear fashion indefinitely or until you run out of reactants. 
B)  The rate of the reaction will increase rapidly, taper off, and plateau. 
C)  The rate of the reaction will increase slowly, plateau, and then drop sharply back to zero. 
D)  The resulting graph will be a perfect bell curve. 
E)  There is no way to predict what the graph will look like without more information.

Question 16

Match between columns
                        Premises: allosteric regulation
activation energy
substrate
catalyst
coupled reaction
transition state
active site
equilibrium point
metabolic pathway

Accepted Answer

The Answer of The linking of an exergonic reaction with is...

Question 17

What is the optimum pH of most enzymes?

Accepted Answer

A)  1 
B)  3 
C)  5 
D)  7 
E)  9 
A)  1 
B)  3 
C)  5 
D)  7 
E)  9

Question 18

The discovery of ____ suggested that nucleic acids likely existed prior to proteins.

Accepted Answer

A)  RNA 
B)  ribozymes 
C)  RNA polymerase 
D)  peptide bonds 
E)  endoplasmic reticulum 
A)  RNA 
B)  ribozymes 
C)  RNA polymerase 
D)  peptide bonds 
E)  endoplasmic reticulum

Question 19

In molecules, the constant motion of the atoms is an example of ____ energy, while the arrangement of atoms and bonds is an example of ____ energy.

Accepted Answer

A)  potential; chemical 
B)  kinetic; potential 
C)  potential; free 
D)  chemical; free 
E)  kinetic; chemical 
A)  potential; chemical 
B)  kinetic; potential 
C)  potential; free 
D)  chemical; free 
E)  kinetic; chemical

Question 20

Is a ribozyme a true enzyme?

Accepted Answer

A)  Yes, because it is a catalyst. 
B)  No, because it is not a protein. 
C)  No, because it cannot catalyze a reaction. 
D)  Yes, because it can synthesize a protein. 
E)  No, because it doesn't require cofactors. 
A)  Yes, because it is a catalyst. 
B)  No, because it is not a protein. 
C)  No, because it cannot catalyze a reaction. 
D)  Yes, because it can synthesize a protein. 
E)  No, because it doesn't require cofactors.

Exam 6: Energy, Enzymes, and Biological Reactions

What is the primary determinant of the function and specificity of an enzyme?

Which statement is a part of the first law of thermodynamics?

Which example would have a negative change in entropy?

The free energy of ATP hydrolysis is -31.0 kJ/mol. The free energy of glucose phosphorylation by hexokinase is +14.3 kJ/mol. These two reactions are coupled to allow them to proceed spontaneously. What is the overall free energy associated with this coupled reaction?

What is the name of the specific region of an enzyme responsible for catalysis?

Define metabolism.

How do cells overcome the energy requirement of endergonic reactions?

The removal of a phosphate group during an enzyme-catalyzed reaction takes ____.

Enzymes aid in metabolism by ____.

What is the ultimate source of energy for almost all organisms?

The rate of catalysis is proportional to the concentration of the enzyme .

At equilibrium, the concentrations of the reactants equals that of the products.

Which statement is true for exergonic reactions?

How does energy coupling allow chemical reactions that are not spontaneous to proceed?

What is the optimum pH of most enzymes?

The discovery of ____ suggested that nucleic acids likely existed prior to proteins.

In molecules, the constant motion of the atoms is an example of ____ energy, while the arrangement of atoms and bonds is an example of ____ energy.

Is a ribozyme a true enzyme?

Introduction to Biological Concepts and Research

Life, Chemistry, and Water

Biological Molecules: the Carbon Compounds of Life

Cells

Membranes and Transport

Cellular Respiration: Harvesting Chemical Energy

Photosynthesis

Cell Communication

Cell Division and Mitosis

Meiosis: the Cellular Basis of Sexual Reproduction

Mendel, Genes, and Inheritance

Genes, Chromosomes, and Human Genetics

Dna Structure, Replication, and Organization

Gene Expression: From Dna to Protein

Regulation of Gene Expression

Bacterial and Viral Genetics

Dna Technology: Making and Using Genetically Altered Organisms, and Other Applications

Genomes and Proteomes

The Development of Evolutionary Thought

Microevolution: Genetic Changes Within Populations

Speciation

Paleobiology and Macroevolution

Systematic Biology: Phylogeny and Classification

The Origin of Life

Prokaryotes and Viruses

Protists

Seedless Plants

Seed Plants

Fungi

Animal Phylogeny, Acoelomates, and Protostomes

Deuterostomes: Vertebrates and Their Closest Relatives

The Plant Body

Transport in Plants

Plant Nutrition

Reproduction and Development in Flowering Plants

Plant Signals and Responses to the Environment

Introduction to Animal Organization and Physiology

Information Flow and the Neuron

Nervous Systems

Sensory Systems

The Endocrine System

Muscles, Bones, and Body Movements

The Circulatory System

Defenses Against Disease

Gas Exchange: the Respiratory System

Digestive Systems and Animal Nutrition

Regulating the Internal Environment: Osmoregulation, Excretion, and Thermoregulation

Animal Reproduction

Animal Development

Ecology and the Biosphere

Population Ecology

Population Interactions and Community Ecology

Ecosystems

Biodiversity and Conservation Biology

Animal Behavior

Filters

In molecules, the constant motion of the atoms is an example of energy, while the arrangement of atoms and bonds is an example of energy.