Question 1

A spontaneous reaction

Accepted Answer

A) has to occur immediately. 
B) will never occur. 
C) has an overall positive free energy change. 
D) could occur but might take a very long time. 
E) is associated exclusively with homeothermic organisms. 
A) has to occur immediately. 
B) will never occur. 
C) has an overall positive free energy change. 
D) could occur but might take a very long time. 
E) is associated exclusively with homeothermic organisms. D

Question 2

Which of the following is a chemoheterotroph?

Accepted Answer

A) grass 
B) a tree 
C) a mushroom 
D) a photosynthetic bacterium 
E) algae 
A) grass 
B) a tree 
C) a mushroom 
D) a photosynthetic bacterium 
E) algae C

Question 3

Compare how energy and matter flow in an ecosystem and relate this flow to the laws of thermodynamics and matter conservation.

Accepted Answer

Although answers will vary,they should contain the following key concepts.The ultimate source of most energy in the biosphere is the sun.Energy flows from the sun,through phototrophs to chemotrophs,and,finally,is dissipated as heat.This reflects the first law of thermodynamics in that the amount of energy remains constant,although the form of energy changes.All of the energy that enters an ecosystem is conserved but eventually dissipates as heat energy.This also upholds the second law of thermodynamics which states that in every physical or chemical change,the universe always tends toward greater disorder.The conversion of the energy in sunlight to heat is an example of an increase in disorder or entropy.Matter,on the other hand,cycles in an ecosystem between phototrophs,chemotrophs,and inorganic chemicals.This upholds the law of the conservation of mass in all physical and chemical changes.In summary,the flow of energy is unidirectional through an ecosystem,while the flow of matter is cyclical.

Question 4

Bioenergetics can be simply defined as

Accepted Answer

A) a subdivision of biology. 
B) applied thermodynamics. 
C) the units in which energy is expressed. 
D) the application of biological principles to physics. 
E) holding constant the variables in the universe. 
A) a subdivision of biology. 
B) applied thermodynamics. 
C) the units in which energy is expressed. 
D) the application of biological principles to physics. 
E) holding constant the variables in the universe.

Question 5

When ΔG' = 0 in a chemical reaction,under standard conditions,

Accepted Answer

A) reactants and products are at equilibrium. 
B) work can be done; energy is required. 
C) the reaction is spontaneous to the left. 
D) no work can be done; no energy is required. 
E) reactants and products are at equilibrium; no work can be done; no energy required. 
A) reactants and products are at equilibrium. 
B) work can be done; energy is required. 
C) the reaction is spontaneous to the left. 
D) no work can be done; no energy is required. 
E) reactants and products are at equilibrium; no work can be done; no energy required.

Question 6

Energy-requiring reactions can occur in biological systems because they can be coupled with reactions that are

Accepted Answer

A) unlikely. 
B) not spontaneous. 
C) endergonic. 
D) exergonic. 
E) spontaneous and endergonic. 
A) unlikely. 
B) not spontaneous. 
C) endergonic. 
D) exergonic. 
E) spontaneous and endergonic.

Question 7

Nerve impulses travel along neurons by the opening of channels that allow sodium ions to flow inward,followed by an outward flow of potassium ions.In order to ensure that the impulse may be produced at any time,sodium is actively transported out of the cell and potassium is transported into the cell by the sodium/potassium pump.Which of the following types of work is performed by the sodium/potassium pump?

Accepted Answer

A) mechanical 
B) electrical 
C) concentration 
D) synthetic 
E) bioluminescent 
A) mechanical 
B) electrical 
C) concentration 
D) synthetic 
E) bioluminescent

Question 8

Which of the following is an endothermic process?

Accepted Answer

A) combustion reactions 
B) adding a strong acid directly to water 
C) oxidation of metals 
D) ice melting 
E) neutralization reactions of the addition of strong acid directly to a strong base 
A) combustion reactions 
B) adding a strong acid directly to water 
C) oxidation of metals 
D) ice melting 
E) neutralization reactions of the addition of strong acid directly to a strong base

Question 9

Fireflies have the ability to convert the energy in ATP to light.Which of the following types of work is performed by the firefly?

Accepted Answer

A) bioluminescent 
B) heat 
C) concentration 
D) electrical 
E) mechanical 
A) bioluminescent 
B) heat 
C) concentration 
D) electrical 
E) mechanical

Question 10

Which of the following statements is false concerning the value ΔH?

Accepted Answer

A) ΔH is the change in heat content. 
B) ΔH is the change in enthalpy. 
C) In biology,ΔH is basically the same as ΔE. 
D) A reaction with a positive ΔH value is exothermic. 
E) ΔH = ΔE + Δ(PV) 
A) ΔH is the change in heat content. 
B) ΔH is the change in enthalpy. 
C) In biology,ΔH is basically the same as ΔE. 
D) A reaction with a positive ΔH value is exothermic. 
E) ΔH = ΔE + Δ(PV)

Question 11

Within biological systems,there are always reactions that seem to occur when thermodynamically they should not.An example is in the process of glycolysis,ΔG°' = 2183.6 kJ/mol.How is this possible,when cells are governed by the laws of thermodynamics?

Accepted Answer

Basically,the conversion of glucose to p

Question 12

Which of the following is defined as "heat content"?

Accepted Answer

A) energy output 
B) heat loss 
C) entropy 
D) solar radiation 
E) enthalpy 
A) energy output 
B) heat loss 
C) entropy 
D) solar radiation 
E) enthalpy

Question 13

When the ΔG°' of a chemical reaction is positive (K'eq < 1.0)under standard conditions,

Accepted Answer

A) reactants and products are at equilibrium. 
B) work can be done under these conditions. 
C) reactants predominate over products. 
D) the reaction is spontaneous to the right. 
E) the reaction is exothermic. 
A) reactants and products are at equilibrium. 
B) work can be done under these conditions. 
C) reactants predominate over products. 
D) the reaction is spontaneous to the right. 
E) the reaction is exothermic.

Question 14

Muscle contraction is an example of which of the following types of work?

Accepted Answer

A) heat 
B) mechanical 
C) bioluminescent 
D) electrical 
E) concentration 
A) heat 
B) mechanical 
C) bioluminescent 
D) electrical 
E) concentration

Question 15

A student drops his notes,and his papers scatter.The fact that the papers scatter and do not remain neatly stacked is an illustration of

Accepted Answer

A) the first law of thermodynamics. 
B) the second law of thermodynamics. 
C) an increase in entropy. 
D) both the first and second laws of thermodynamics. 
E) an increase in entropy as predicted by the second law of thermodynamics. 
A) the first law of thermodynamics. 
B) the second law of thermodynamics. 
C) an increase in entropy. 
D) both the first and second laws of thermodynamics. 
E) an increase in entropy as predicted by the second law of thermodynamics.

Question 16

Bioluminescence can be driven by

Accepted Answer

A) green fluorescent protein. 
B) ATP. 
C) chemical oxidation. 
D) either ATP or chemical oxidation. 
E) mushrooms. 
A) green fluorescent protein. 
B) ATP. 
C) chemical oxidation. 
D) either ATP or chemical oxidation. 
E) mushrooms.

Question 17

Which process involves an increase in entropy of the system?

Accepted Answer

A) freezing of ice 
B) any spontaneous process 
C) combustion of paper 
D) formation of raindrops 
E) synthesis of cellulose 
A) freezing of ice 
B) any spontaneous process 
C) combustion of paper 
D) formation of raindrops 
E) synthesis of cellulose

Question 18

Which is true of heterotrophs?

Accepted Answer

A) They capture light energy. 
B) They cannot be unicellular. 
C) They store energy in the form of heat. 
D) They can function as autotrophs in an emergency. 
E) They can obtain energy by consuming phototrophs. 
A) They capture light energy. 
B) They cannot be unicellular. 
C) They store energy in the form of heat. 
D) They can function as autotrophs in an emergency. 
E) They can obtain energy by consuming phototrophs.

Question 19

Animals that regulate their body temperature independently of the environment are called

Accepted Answer

A) heterotherms. 
B) homeotherms. 
C) poikilotherms. 
D) biotherms. 
E) abiotherms. 
A) heterotherms. 
B) homeotherms. 
C) poikilotherms. 
D) biotherms. 
E) abiotherms.

Question 20

In a cell,the concentration of glucose-6-phosphate is 83 ?M and of fructose-6-phosphate is 14 ?M.The ?G°' = 410 cal/mol for the conversion of glucose-6-phosphate to fructose-6-phosphate.Based upon this information,the ?G' for this reaction (in cal/mol)is

Accepted Answer

A) ?644. 
B) ?63.7. 
C) 0. 
D) 27. 
E) 644. 
A) ?644. 
B) ?63.7. 
C) 0. 
D) 27. 
E) 644.

Exam 5: Bioenergetics: the Flow of Energy in the Cell

A spontaneous reaction

Which of the following is a chemoheterotroph?

Compare how energy and matter flow in an ecosystem and relate this flow to the laws of thermodynamics and matter conservation.

Bioenergetics can be simply defined as

When ΔG' = 0 in a chemical reaction,under standard conditions,

Energy-requiring reactions can occur in biological systems because they can be coupled with reactions that are

Which of the following is an endothermic process?

Fireflies have the ability to convert the energy in ATP to light.Which of the following types of work is performed by the firefly?

Which of the following statements is false concerning the value ΔH?

Within biological systems,there are always reactions that seem to occur when thermodynamically they should not.An example is in the process of glycolysis,ΔG°' = 2183.6 kJ/mol.How is this possible,when cells are governed by the laws of thermodynamics?

Which of the following is defined as "heat content"?

When the ΔG°' of a chemical reaction is positive (K'eq < 1.0)under standard conditions,

Muscle contraction is an example of which of the following types of work?

A student drops his notes,and his papers scatter.The fact that the papers scatter and do not remain neatly stacked is an illustration of

Bioluminescence can be driven by

Which process involves an increase in entropy of the system?

Which is true of heterotrophs?

Animals that regulate their body temperature independently of the environment are called

In a cell,the concentration of glucose-6-phosphate is 83 ?M and of fructose-6-phosphate is 14 ?M.The ?G°' = 410 cal/mol for the conversion of glucose-6-phosphate to fructose-6-phosphate.Based upon this information,the ?G' for this reaction (in cal/mol)is

A Preview of Cell Biology

The Chemistry of the Cell

The Macromolecules of the Cell

Cells and Organelles

Enzymes: the Catalysts of Life

Membranes: Their Structure,function,and Chemistry

Transport Across Membranes: Overcoming the Permeability Barrier

Chemotrophic Energy Metabolism: Glycolysis and Fermentation

Chemotrophic Energy Metabolism: Aerobic Respiration

Phototrophic Energy Metabolism: Photosynthesis

The Endomembrane System

Cytoskeletal Systems

Cellular Movement: Motility and Contractility

Beyond the Cell: Cell Adhesions, cell Junctions, and Extracellular Structures

The Structural Basis of Cellular Information: Dna, chromosomes, and the Nucleus

DNA Replication, repair, and Recombination

Gene Expression: Ithe Genetic Code and Transcription

Gene Expression: Iiprotein Synthesis and Sorting

The Regulation of Gene Expression

Molecular Biology Techniques for Cell Biology

Signal Transduction Mechanisms: Ielectrical and Synaptic Signaling in Neurons

Signal Transduction Mechanisms: Iimessengers and Receptors

The Cell Cycle and Mitosis

Sexual Reproduction,meiosis,and Genetic Recombination

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When the ΔG°' of a chemical reaction is positive (K'_eq < 1.0)under standard conditions,