Campbell s Biology 9e Reece et al Chapter 8 An Introduction to Metabolism This chapter lays the foundations for the chapters on respiration and photosynthesis Key concepts are as follows The laws of thermodynamics govern energy transformations by living organisms metabolic reactions couple energy harvesting reactions to reactions that accomplish cellular work and enzymes increase the rates of reaction Understanding the properties of enzymes how they work and how their activities are regulated is necessary to achieve an understanding of metabolic pathways Multiple Choice Questions 1 Which term most precisely describes the cellular process of breaking down large molecules into smaller ones A catalysis B metabolism C anabolism D dehydration E catabolism Answer E Topic Concept 8 1 Skill Knowledge Comprehension 2 Which of the following is are true for anabolic pathways A They do not depend on enzymes B They are usually highly spontaneous chemical reactions C They consume energy to build up polymers from monomers D They release energy as they degrade polymers to monomers E They consume energy to decrease the entropy of the organism and its environment Answer C Topic Concept 8 1 Skill Knowledge Comprehension 3 Which of the following is a statement of the first law of thermodynamics A Energy cannot be created or destroyed B The entropy of the universe is decreasing C The entropy of the universe is constant D Kinetic energy is stored energy that results from the specific arrangement of matter E Energy cannot be transferred or transformed Answer A Topic Concept 8 1 Skill Knowledge Comprehension 1 Copyright 2011 Pearson Education Inc 4 For living organisms which of the following is an important consequence of the first law of thermodynamics A The energy content of an organism is constant B The organism ultimately must obtain all of the necessary energy for life from its environment C The entropy of an organism decreases with time as the organism grows in complexity D Organisms grow by converting energy into organic matter E Life does not obey the first law of thermodynamics Answer B Topic Concept 8 1 Skill Synthesis Evaluation 5 Living organisms increase in complexity as they grow resulting in a decrease in the entropy of an organism How does this relate to the second law of thermodynamics A Living organisms do not obey the second law of thermodynamics which states that entropy must increase with time B Life obeys the second law of thermodynamics because the decrease in entropy as the organism grows is exactly balanced by an increase in the entropy of the universe C Living organisms do not follow the laws of thermodynamics D As a consequence of growing organisms cause a greater increase in entropy in their environment than the decrease in entropy associated with their growth E Living organisms are able to transform energy into entropy Answer D Topic Concept 8 1 Skill Synthesis Evaluation 6 Whenever energy is transformed there is always an increase in the 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 Answer D Topic Concept 8 1 Skill Knowledge Comprehension 7 Which of the following statements is a logical consequence of the second law of thermodynamics 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 Answer D Topic Concept 8 1 Skill Synthesis Evaluation 2 Copyright 2011 Pearson Education Inc 8 Which of the following statements is representative of the second law of thermodynamics 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 Answer D Topic Concept 8 1 Skill Knowledge Comprehension 9 Which of the following types of reactions would decrease the entropy within a cell A anabolic reactions B hydrolysis C respiration D digestion E catabolic reactions Answer A Topic Concept 8 1 Skill Application Analysis 10 Biological evolution of life on Earth from simple prokaryote like cells to large multicellar eukaryotic organisms 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 Answer A Topic Concept 8 1 Skill Knowledge Comprehension 11 Which of the following is an example of potential rather than kinetic energy A the muscle contractions of a person mowing grass B water rushing over Niagara Falls C light flashes emitted by a firefly D a molecule of glucose E the flight of an insect foraging for food Answer D Topic Concept 8 1 Skill Knowledge Comprehension 3 Copyright 2011 Pearson Education Inc 12 Which of the following is the smallest closed system A a cell B an organism C an ecosystem D Earth E the universe Answer E Topic Concept 8 1 Skill Knowledge Comprehension 13 Which of the following is true of metabolism in its entirety in all organisms A Metabolism depends on a constant supply of energy from food B Metabolism depends on an organism s adequate hydration C Metabolism uses all of an organism s resources D Metabolism consists of all the energy transformation reactions in an organism E Metabolism manages the increase of entropy in an organism Answer D Topic Concepts 8 1 8 5 Skill Synthesis Evaluation 14 The mathematical expression for the change in free energy of a system is G H T S Which of the following is are correct A S is the change in enthalpy a measure of randomness B H is the change in entropy the energy available to do work C G is the change in free energy D T is the temperature in