Exam 2 Cellular And Molecular Biology

54 Questions | Total Attempts: 1369

SettingsSettingsSettings
Please wait...
Exam 2 Cellular And Molecular Biology

Biol 218Exam 2Cellular and Molecular Biology


Questions and Answers
  • 1. 
    The sodium-potassium pump makes the cell interior more______ by pumping ____ sodium ions out of the cell for every____ potassium ions pumped in.
    • A. 

      Negative, 3, 2

    • B. 

      Negative, 2, 3

    • C. 

      Positive, 3, 2

    • D. 

      Positive, 2, 3

    • E. 

      Negative, 4, 3

  • 2. 
    • A. 

      It must be pumped during the cycle.

    • B. 

      It must be phosphorylated during the cycle

    • C. 

      It must be protonated during the cycle

    • D. 

      It must be deprotonated during the cycle

    • E. 

      It must be potassiumated during the cycle

  • 3. 
    In the Na+/glucose cotransporter, _____ moving down its/theirgradient drive the transport of _____ against its/their gradient.
    • A. 

      Na+ ions, K+ ions

    • B. 

      Na+ ions, glucose

    • C. 

      Glucose, Na+ ions

    • D. 

      K+ ions, glucose

    • E. 

      Glucose, K+ ions

  • 4. 
    • A. 

      Succinate dehydrogenase, mitochondrial matrix

    • B. 

      Malate dehydrogenase, mitochondrial matrix

    • C. 

      Succinate dehydrogenase, inner mitochondrial membrane

    • D. 

      Malate dehydrogenase, inner mitochondrial membrane

    • E. 

      Succinate dehydrogenase, intermembrane space

  • 5. 
    The movement of water through a semipermeable membranefrom a region of higher water concentration to a region of lowerwater concentration is called ________.
    • A. 

      Diffusion

    • B. 

      Osmosis

    • C. 

      Denaturation

    • D. 

      Metabolism

    • E. 

      Solubility

  • 6. 
    The phosphorylation of glucose to generate glucose-6-phosphate is catalyzed by the enzyme hexokinase. This enzyme,however, is inhibited by its own product, glucose-6-phosphate.This is an example of:
    • A. 

      Allosteric regulation

    • B. 

      Irreversible inhibition

    • C. 

      Non-covalent modification

    • D. 

      Feedback regulation

    • E. 

      Covalent modification

  • 7. 
    A protein extract containing an enzyme of interest is preparedfrom a tissue. The enzyme activity is tested using a panel ofsuspected substrates. However the enzyme is not active, leadingto the conclusion that none of the compounds is the enzyme’ssubstrate. One student of Biol218-003 suggests adding ATP tothe enzyme mixture. Suddenly a reaction is observed in one ofthe tubes. After adding ATP the enzyme was purified and one ofits aminoacids has a phosphate group. This is an example of
    • A. 

      Lucky guess

    • B. 

      Covalent modification of enzymes

    • C. 

      Activation of the enzymatic activity by a kinase

    • D. 

      B and c

  • 8. 
    A transport system that moves two solutes into the cell during asingle cycle accompanied by no expenditure of energy could becalled a(n) ________
    • A. 

      Active antiport

    • B. 

      Active uniport

    • C. 

      Passive antiport

    • D. 

      Active symport

    • E. 

      Passive symport

  • 9. 
    Feedback inhibitors bind to the
    • A. 

      Allosteric site

    • B. 

      Active site

    • C. 

      Substrate

    • D. 

      Cofactor

    • E. 

      A and b

  • 10. 
    The inner membrane of the mitochondria has a high protein tolipid ratio because it contains ____________.
    • A. 

      Electron transport chain

    • B. 

      ATP synthase

    • C. 

      Cardiolysin

    • D. 

      A and b

    • E. 

      A and c

  • 11. 
    What is the purpose of uncoupling proteins in mammalian brownadipose tissue (baby fat)?
    • A. 

      They help the tissue expand and contract when needed.

    • B. 

      They function as a source of heat production during exposure to cold temperatures.

    • C. 

      They allow the production of a larger number of ATPs per glucose.

    • D. 

      They allow muscles to contract more efficiently.

    • E. 

      They give the tissue its color.

  • 12. 
    Which molecule below plays a key role in regulating the rate ofglycolysis and Krebs cycle by regulating the activity of keyenzymes?
    • A. 

      ADP

    • B. 

      ATP

    • C. 

      Inorganic Phosphate

    • D. 

      Molecular oxygen

    • E. 

      None of the above

  • 13. 
    Metabolic pathways that make available raw materials fromwhich other molecules can be synthesized and that providechemical energy required for many cell activities are known as______.
    • A. 

      Anabolism

    • B. 

      Catabolism

    • C. 

      Manabolism

    • D. 

      Allosterism

  • 14. 
    A reaction involving the gain of one or more electrons is a(n)_________ reaction.
    • A. 

      Oxidation

    • B. 

      Reduction

    • C. 

      Inclusion

    • D. 

      Elimination

    • E. 

      None of the above

  • 15. 
    In order to take full advantage of the energy released during anexergonic reation, it is ______________.
    • A. 

      Done in small steps

    • B. 

      Used to drive the temperature of the cells up

    • C. 

      Coupled to an endergonic reaction

    • D. 

      Coupled to another exergonic reaction

  • 16. 
    Which of the following is the primary function of fermentation?
    • A. 

      Completely break down a glucose molecule to carbon dioxide and water

    • B. 

      Produce ATP by chemiosmosis

    • C. 

      Oxidize NAD+ to NADH

    • D. 

      Oxidize NADH to NAD+

    • E. 

      All of the above

  • 17. 
    Which reaction below might be a suitable coupled reaction for thereaction A + B <—> C + D (ÄG = +6.7 kcal/mole)?
    • A. 

      E + F G + H (ÄG = -5.4 kcal/mole)

    • B. 

      C + F G + H (ÄG = -5.4 kcal/mole)

    • C. 

      E + F G + H (ÄG = -8.3 kcal/mole)

    • D. 

      E + F G + H (ÄG = -9.7 kcal/mole)

    • E. 

      None of them

  • 18. 
    The outer membrane of the mitochondria has large channelssurrounded by a Beta barrel called _________________.
    • A. 

      Proton pump

    • B. 

      Cardiolipin

    • C. 

      Porins

    • D. 

      Cytochrome complex

    • E. 

      ATP synthesis

  • 19. 
    The redox centers of most of the proteins of the respiratory chainare made up of _________________.
    • A. 

      Flavoproteins

    • B. 

      Vitamins

    • C. 

      Prosthetic groups

    • D. 

      Cytochromes

    • E. 

      Ubiquinone

  • 20. 
    An electrochemical gradient is caused by __________________.
    • A. 

      Energy distribution

    • B. 

      Voltage gradient

    • C. 

      Concentration gradient

    • D. 

      A and b

    • E. 

      B and c

  • 21. 
    Which molecule is the final electron acceptor in the electrontransport chain?
    • A. 

      ATP

    • B. 

      Water

    • C. 

      NADH

    • D. 

      Oxygen

    • E. 

      FADH2

  • 22. 
    Diffusion during which the substance to be transported bindsselectively to a membrane-spanning protein, which helps theprocess along, is called ________.
    • A. 

      Osmosis

    • B. 

      Facilitated Osmosis

    • C. 

      Simple Diffusion

    • D. 

      Facilitated Diffusion

    • E. 

      Active Transport

  • 23. 
    An important aspect of transport by facilitated transporters andpumps is
    • A. 

      Conformational shifts

    • B. 

      Rigidity softness

    • C. 

      á-helix

    • D. 

      B-pleated sheet

  • 24. 
    The site of aerobic respiration (electron transport chain) and ATPformation is in the _________________ of the Mitochondria.
    • A. 

      Outer membrane

    • B. 

      Matrix

    • C. 

      Inner membrane

    • D. 

      Intermembrane space

  • 25. 
    One mechanism (or class of molecules) by which ions arespecifically transported into the cell is the
    • A. 

      Induced fit model

    • B. 

      Gated channels

    • C. 

      Carrier protein transport

    • D. 

      Uniport transport

    • E. 

      All of the above