Chapter 8

Last update by mayur on 03/27/2014
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A chemical reaction that has a positive

Answer:

A) endergonic.(absorption of energy)


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    Answered in Chapter 8

    Which of the following best describes enthalpy (H)? 

    A) the total kinetic energy of a system 

    B) the heat content of a chemical system 

    C) the system's entropy 

    D) the cell's energy equilibrium 

    E) the condition of a cell that is not able to react 



    B) the heat content of a chemical system 



  • feldman2009
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    Why is ATP an important molecule in metabolism? 

    A) Its hydrolysis provides an input of free energy for exergonic reactions. 

    B) It provides energy coupling between exergonic and endergonic reactions. 

    C) Its terminal phosphate group contains a strong covalent bond that when hydrolyzed releases free energy. 

    D) Its terminal phosphate bond has higher energy than the other two. 

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  • feldman2009
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    When 10,000 molecules of ATP are hydrolyzed to ADP and Pi in a test tube, about twice as much heat is liberated as when a cell hydrolyzes the same amount of ATP. Which of the following is the best explanation for this observation? 

    A) Cells are open systems, but a test tube is a closed system. 

    B) Cells are less efficient at heat production than nonliving systems. 

    C) The hydrolysis of ATP in a cell produces different chemical products than does the reaction in a test tube. 

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    E) Reactant and product concentrations are not the same 
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    Which of the following is most similar in structure to ATP? 

    A) an anabolic steroid 

    B) a DNA helix 

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    E) a phospholipid 



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  • feldman2009
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    What term is used to describe the transfer of free energy from catabolic pathways to anabolic pathways? 

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    D) entropy 

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    C) energy coupling 



  • feldman2009
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    Which of the following statements is true concerning catabolic pathways? 

    A) They combine molecules into more energy-rich molecules. 

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  • feldman2009
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    When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated? 

    A) It is used to power yet more cellular work. 

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    When ATP releases some energy, it also releases inorganic phosphate. What purpose does this serve (if any) in the cell? 

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    D) It can be added to other molecules in order to activate them. 



  • feldman2009
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    What must be the difference (if any) between the structure of ATP and the structure of the precursor of the A nucleotide in DNA and RNA? 

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    B) The nitrogen-containing base is different. 

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    Which of the following statements is (are) true about enzyme-catalyzed reactions? 

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