Lab 5: Cellular Respiration

  1. What are the three ways you can measure cellular respiration?
    • 1) consumption of O2
    • 2) production of CO2
    • 3) Release of energy
  2. PV= nRT

    What does everything symbolize?
    • pressure
    • volume
    • number of gas molecules
    • gas constant
    • temp
  3. If temp and pressure are kept constant, then the __ is directly proportional to the number of molecules of the gas?
    volume of the gas
  4. If the temp and volume remain constant, then the __ changes in direct proportion to the number of gas molecules present.
  5. If the number of gas moleules and the temp remain constant, then the __ is inversely proportional to the __.
    • pressure
    • volume
  6. If the temp changes and teh number of gas molecules is kept constant, then either _ or __ or both will change in direct proportion to the __.
    • pressure
    • volume
    • temp
  7. In the experiment, what will happen to CO2?
    it will be removed by KOH and will form solid potassium carbonate
  8. Since the CO2 is being removed, the cange in volume of gas in the respirometer will be directly related to the amount of __.
    oxygen consumed
  9. During respiration, oxygen will be consumed. Its __ will be reduced, because the CO2 produced is being converted into a solid. The net result is a decrease in gas volume within he tune, and a related decrease in pressure in the tube.
  10. This lab uses a number of controls. Name some and describe their purpose.
    • Volume of KOH is equal in every tube: this will correct for any volume differences. ITs purpose to remove CO2 and form K2CO3
    • The temp should remain constant for the vials: the ones held at 10 should remain at 10, and the ones at room temp should remain at that temp. This should occur because we are testing a hypothesis based on temp also.
    • Accurate time intervals: we should have remained an equilibrium period of seven minutes; any time above this might have altered the results
    • Pressure should have also remained constant.
  11. What is the independent variable in this experiment? dependent?
    • ind: time
    • dep: volume
  12. Describe and explain the relationship between the amount of O2 consumed and time.
    Over time, O2 consumption would increase. Also, O2 consumption was greater in warmer temperature than in colder temperature and in germinating peas over non.
  13. If you used the same experimental design to compare the rates of respiration of a 25 g. reptile and a 25 g. mammal at 10oC, what results woul dyou expect?
    resp higher in mammal because the reptile is a conformer and relies on the environment for its warmth. Whatever the environment is, thats what the reptile will adjust his metabolic to. However, the mammal has an internal mechanism to maintain body temperature. So, at low temps, they will increase body temp becasue they need to keep warm.
  14. IF respiration in a small mammal were studied at both room temp (21 C) and 10 C, what results would you predict? Explain your reasoning.
    Respiration would be higher in room temp because at higher temp, they can use the heat from the environment as well as its metabolism to maintain their body temp. At 10 C, however, their cell resp would proliferate because they must use alot of energy to try to keep warm, especially since the environment isnt helping them. THis requires much more work.
  15. Explain why water moved into teh respirometers' meters.
    • Water moved into the respirometer's meters because there was a decrease in volume and pressure. BEcause volume and pressure move to where there is less, they moved into the vials. There was less volume because O2 was being produced and CO2 was being consumed. But since CO2 was being (removed) converted into a solid potassium carbonate, volume was directly proportional to the oxygen consumption. Because oxygen was being consumed, it was causing a decrease in volume, causing water to move in to try to balance it out.
    • Pressure also plays a part because pressure is lesss in the vial since O2 is being consumed, providing that space allowing water to enter.
Card Set
Lab 5: Cellular Respiration
AP Bio