Question 1

Whenever energy is transformed,there is always an increase in the

Accepted Answer

A) free energy of the system. 
B) free energy of the universe. 
C) entropy of the system. 
D) entropy of the universe. 
E) enthalpy of the universe. 
A) free energy of the system. 
B) free energy of the universe. 
C) entropy of the system. 
D) entropy of the universe. 
E) enthalpy of the universe.

Question 2

A system at chemical equilibrium

Accepted Answer

A) consumes energy at a steady rate. 
B) releases energy at a steady rate. 
C) consumes or releases energy, depending on whether it is exergonic or endergonic. 
D) has zero kinetic energy. 
E) can do no work. 
A) consumes energy at a steady rate. 
B) releases energy at a steady rate. 
C) consumes or releases energy, depending on whether it is exergonic or endergonic. 
D) has zero kinetic energy. 
E) can do no work.

Question 3

Use the following information to answer the questions below.
A patient comes into the emergency room having accidentally ingested methanol (a component in anti-freeze).The products of methanol degradation are toxic,and can lead to blindness,neurological issues,or death.However,if methanol degradation can be slowed down,the toxic by-products do not have a chance to accumulate.ADH has a higher affinity to ethanol,where it functions to oxidize ethanol into acetaldehyde with the end product of the pathway being acetic acid (vinegar).
-Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism as ________ is to ________.

Accepted Answer

A) exergonic; spontaneous 
B) exergonic; endergonic 
C) free energy; entropy 
D) work; energy 
E) entropy; enthalpy 
A) exergonic; spontaneous 
B) exergonic; endergonic 
C) free energy; entropy 
D) work; energy 
E) entropy; enthalpy

Question 4

Which of the following statements regarding enzymes is true?

Accepted Answer

A) Enzymes increase the rate of a reaction by making the reaction more exergonic. 
B) Enzymes increase the rate of a reaction by lowering the activation energy barrier. 
C) Enzymes increase the rate of a reaction by reducing the rate of reverse reactions. 
D) Enzymes change the equilibrium point of the reactions they catalyze. 
E) Enzymes make the rate of a reaction independent of substrate concentrations. 
A) Enzymes increase the rate of a reaction by making the reaction more exergonic. 
B) Enzymes increase the rate of a reaction by lowering the activation energy barrier. 
C) Enzymes increase the rate of a reaction by reducing the rate of reverse reactions. 
D) Enzymes change the equilibrium point of the reactions they catalyze. 
E) Enzymes make the rate of a reaction independent of substrate concentrations.

Question 5

Chemical equilibrium is relatively rare in living cells.Which of the following could be an example of a reaction at chemical equilibrium in a cell?

Accepted Answer

A) a reaction in which the free energy at equilibrium is higher than the energy content at any point away from equilibrium 
B) a chemical reaction in which the entropy change in the reaction is just balanced by an opposite entropy change in the cell's surroundings 
C) an endergonic reaction in an active metabolic pathway where the energy for that reaction is supplied only by heat from the environment 
D) a chemical reaction in which both the reactants and products are not being produced or used in any active metabolic pathway 
E) no possibility of having chemical equilibrium in any living cell 
A) a reaction in which the free energy at equilibrium is higher than the energy content at any point away from equilibrium 
B) a chemical reaction in which the entropy change in the reaction is just balanced by an opposite entropy change in the cell's surroundings 
C) an endergonic reaction in an active metabolic pathway where the energy for that reaction is supplied only by heat from the environment 
D) a chemical reaction in which both the reactants and products are not being produced or used in any active metabolic pathway 
E) no possibility of having chemical equilibrium in any living cell

Question 6

Use the following information to answer the questions below.
Succinate dehydrogenase catalyzes the conversion of succinate to fumarate.The reaction is inhibited by malonic acid,which resembles succinate but cannot be acted upon by succinate dehydrogenase.Increasing the ratio of succinate to malonic acid reduces the inhibitory effect of malonic acid.
-Based on this information,which of the following is correct?

Accepted Answer

A) Succinate dehydrogenase is the enzyme, and fumarate is the substrate. 
B) Succinate dehydrogenase is the enzyme, and malonic acid is the substrate. 
C) Succinate is the substrate, and fumarate is the product. 
D) Fumarate is the product, and malonic acid is a noncompetitive inhibitor. 
E) Malonic acid is the product, and fumarate is a competitive inhibitor. 
A) Succinate dehydrogenase is the enzyme, and fumarate is the substrate. 
B) Succinate dehydrogenase is the enzyme, and malonic acid is the substrate. 
C) Succinate is the substrate, and fumarate is the product. 
D) Fumarate is the product, and malonic acid is a noncompetitive inhibitor. 
E) Malonic acid is the product, and fumarate is a competitive inhibitor.

Question 7

Some bacteria are metabolically active in hot springs because

Accepted Answer

A) they are able to maintain a lower internal temperature. 
B) high temperatures make catalysis unnecessary. 
C) their enzymes have high optimal temperatures. 
D) their enzymes are completely insensitive to temperature. 
E) they use molecules other than proteins or RNAs as their main catalysts. 
A) they are able to maintain a lower internal temperature. 
B) high temperatures make catalysis unnecessary. 
C) their enzymes have high optimal temperatures. 
D) their enzymes are completely insensitive to temperature. 
E) they use molecules other than proteins or RNAs as their main catalysts.

Question 8

Use the following information to answer the questions below.
   
Activity of various enzymes at various temperatures (a)and at various pH (b).
-Which temperature and pH profile curves on the graphs were most likely generated from analysis of an enzyme from a human stomach where conditions are strongly acid?

Accepted Answer

A) curves 1 and 4 
B) curves 1 and 5 
C) curves 2 and 4 
D) curves 2 and 5 
E) curves 3 and 4 
A) curves 1 and 4 
B) curves 1 and 5 
C) curves 2 and 4 
D) curves 2 and 5 
E) curves 3 and 4

Question 9

Use the following information to answer the questions below.
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.
-With respect to the enzyme that converts X to Y,substance A functions as

Accepted Answer

A) a coenzyme. 
B) an allosteric inhibitor. 
C) the substrate. 
D) an intermediate. 
E) a competitive inhibitor. 
A) a coenzyme. 
B) an allosteric inhibitor. 
C) the substrate. 
D) an intermediate. 
E) a competitive inhibitor.

Question 10

What is the kinetic energy associated with the random movement of atoms called?

Accepted Answer

A) entropy 
B) work 
C) chemical energy 
D) thermal energy 
E) heat 
A) entropy 
B) work 
C) chemical energy 
D) thermal energy 
E) heat

Question 11

Which of the following statements is a logical consequence of the second law of thermodynamics?

Accepted Answer

A) If the entropy of a system increases, there must be a corresponding decrease in the entropy of the universe. 
B) If there is an increase in the energy of a system, there must be a corresponding decrease in the energy of the rest of the universe. 
C) Every energy transfer requires activation energy from the environment. 
D) Every chemical reaction must increase the total entropy of the universe. 
E) Energy can be transferred or transformed, but it cannot be created or destroyed. 
A) If the entropy of a system increases, there must be a corresponding decrease in the entropy of the universe. 
B) If there is an increase in the energy of a system, there must be a corresponding decrease in the energy of the rest of the universe. 
C) Every energy transfer requires activation energy from the environment. 
D) Every chemical reaction must increase the total entropy of the universe. 
E) Energy can be transferred or transformed, but it cannot be created or destroyed.

Question 12

Which of the following is the smallest closed system?

Accepted Answer

A) a cell 
B) an organism 
C) an ecosystem 
D) Earth 
E) the universe 
A) a cell 
B) an organism 
C) an ecosystem 
D) Earth 
E) the universe

Question 13

The following questions are based on the reaction A + B ↔ C + D shown in the figure below.
  
-Which of the following represents the activation energy needed for the noncatalyzed reverse reaction,C + D → A + B,in the figure above?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) e 
A) a 
B) b 
C) c 
D) d 
E) e

Question 14

Which of the following statements is representative of the second law of thermodynamics?

Accepted Answer

A) Conversion of energy from one form to another is always accompanied by some gain of free energy. 
B) Heat represents a form of energy that can be used by most organisms to do work. 
C) Without an input of energy, organisms would tend toward decreasing entropy. 
D) Cells require a constant input of energy to maintain their high level of organization. 
E) Every energy transformation by a cell decreases the entropy of the universe. 
A) Conversion of energy from one form to another is always accompanied by some gain of free energy. 
B) Heat represents a form of energy that can be used by most organisms to do work. 
C) Without an input of energy, organisms would tend toward decreasing entropy. 
D) Cells require a constant input of energy to maintain their high level of organization. 
E) Every energy transformation by a cell decreases the entropy of the universe.

Question 15

Biological evolution of life on Earth,from simple prokaryote-like cells to large,multicellular eukaryotic organisms

Accepted Answer

A) has occurred in accordance with the laws of thermodynamics. 
B) has caused an increase in the entropy of the planet. 
C) has been made possible by expending Earth's energy resources. 
D) has occurred in accordance with the laws of thermodynamics, by expending Earth's energy resources and causing an increase in the entropy of the planet. 
E) violates the laws of thermodynamics because Earth is a closed system. 
A) has occurred in accordance with the laws of thermodynamics. 
B) has caused an increase in the entropy of the planet. 
C) has been made possible by expending Earth's energy resources. 
D) has occurred in accordance with the laws of thermodynamics, by expending Earth's energy resources and causing an increase in the entropy of the planet. 
E) violates the laws of thermodynamics because Earth is a closed system.

Question 16

Which of the following is true of enzymes?

Accepted Answer

A) Nonprotein cofactors alter the substrate specificity of enzymes. 
B) Enzyme function is increased if the 3-D structure or conformation of an enzyme is altered. 
C) Enzyme function is independent of physical and chemical environmental factors such as pH and temperature. 
D) Enzymes increase the rate of chemical reaction by lowering activation energy barriers. 
E) Enzymes increase the rate of chemical reaction by providing activation energy to the substrate. 
A) Nonprotein cofactors alter the substrate specificity of enzymes. 
B) Enzyme function is increased if the 3-D structure or conformation of an enzyme is altered. 
C) Enzyme function is independent of physical and chemical environmental factors such as pH and temperature. 
D) Enzymes increase the rate of chemical reaction by lowering activation energy barriers. 
E) Enzymes increase the rate of chemical reaction by providing activation energy to the substrate.

Question 17

Organisms can increase their order,seemingly defying the second law of thermodynamics.This can only be accomplished if they

Accepted Answer

A) are a closed system. 
B) constantly take energy from their surroundings and thus increase disorder in the environment. 
C) constantly take energy from their surroundings and thus decrease disorder in the environment. 
D) generate heat and increase disorder in the universe. 
E) have a negative Gibbs free energy value. 
A) are a closed system. 
B) constantly take energy from their surroundings and thus increase disorder in the environment. 
C) constantly take energy from their surroundings and thus decrease disorder in the environment. 
D) generate heat and increase disorder in the universe. 
E) have a negative Gibbs free energy value.

Question 18

How might an amino acid change at a site distant from the active site of the enzyme alter the enzyme's substrate specificity?

Accepted Answer

A) by changing the enzyme's stability 
B) by changing the enzyme's location in the cell 
C) by changing the shape of the protein 
D) by changing the enzyme's pH optimum 
E) an amino acid change away from the active site cannot alter the enzyme's substrate specificity 
A) by changing the enzyme's stability 
B) by changing the enzyme's location in the cell 
C) by changing the shape of the protein 
D) by changing the enzyme's pH optimum 
E) an amino acid change away from the active site cannot alter the enzyme's substrate specificity

Question 19

A chemical agent that speeds up a reaction without being consumed during the reaction is known as a(n)

Accepted Answer

A) enhancer 
B) substrate 
C) co-enzyme 
D) reactant 
E) catalyst 
A) enhancer 
B) substrate 
C) co-enzyme 
D) reactant 
E) catalyst

Question 20

Which of the following contributes to the instability of ATP?

Accepted Answer

A) demand by the cell to use phosphate in other chemical reactions 
B) insolubility of adenine in water 
C) weak ionic bond 
D) weak covalent bond 
E) repulsion between phosphate groups 
A) demand by the cell to use phosphate in other chemical reactions 
B) insolubility of adenine in water 
C) weak ionic bond 
D) weak covalent bond 
E) repulsion between phosphate groups

Exam 8: An Introduction to Metabolism

Whenever energy is transformed,there is always an increase in the

A system at chemical equilibrium

Which of the following statements regarding enzymes is true?

Chemical equilibrium is relatively rare in living cells.Which of the following could be an example of a reaction at chemical equilibrium in a cell?

Some bacteria are metabolically active in hot springs because

What is the kinetic energy associated with the random movement of atoms called?

Which of the following statements is a logical consequence of the second law of thermodynamics?

Which of the following is the smallest closed system?

The following questions are based on the reaction A + B ↔ C + D shown in the figure below. -Which of the following represents the activation energy needed for the noncatalyzed reverse reaction,C + D → A + B,in the figure above?

Which of the following statements is representative of the second law of thermodynamics?

Biological evolution of life on Earth,from simple prokaryote-like cells to large,multicellular eukaryotic organisms

Which of the following is true of enzymes?

Organisms can increase their order,seemingly defying the second law of thermodynamics.This can only be accomplished if they

How might an amino acid change at a site distant from the active site of the enzyme alter the enzyme's substrate specificity?

A chemical agent that speeds up a reaction without being consumed during the reaction is known as a(n)

Which of the following contributes to the instability of ATP?

Introduction: Evolution and Themes of Biology

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure,Growth,and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons,Synapses,and Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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