STANDARDS:
    maximum points = 10
 
  DATA RECORD AND CALCULATIONS
    GRAPH           axis X = Time (ind); Y = Product (dep)  3 pts
               scale and label axis
               curve plotted - drawn curve necessary
    a.  initial rate          1 pt. setup (.25-.00)/(10-0)  2 pts
         0.025 mg/sec              or    (.50-.00)/(20-0)
            .25  mg/10 sec           or    number 0.025
           1.5   mg/min  1 pt. units (mg/sec) or mg/min)
           1/40 mg/sec
    b.  rate after 50 sec                                   1 pt
     Zero      1 pt. set up (.85-.85)/(60-50)
                      or      1 pt. units if not awarded in part a.
     net rate
     equilibrium
 
     Why?                                    1 pt
       Substrate gone or reaction at equilibrium
       Other explanation - any are possible
          Product inhibition
          Product changes pH or temp optimum
          Product release time varies             Maximum = 7 pts
 
  EXPLANATIONS:
  c. Temperature variation
     Change: stops reaction; no product formation;          1 pt
          rate near or at zero
     Explanation: Conformational shape change - denaturation     1 pt
          (inactivation - "kills" in quotes)
 
  d. Substrate concentration variation;
     Change:                                 1 pt
          (Increase) a) no change, initial slope same;
                      longer to level off;
                      or b) increase in reaction rate
          and/or
          (Decrease) more gentle slope; decrease rate or take less time to level off;
     Explanation:                            1 pt
          (Increase) a) Enzyme is working as fast as it can (Vmax)
                        or b) It will approach Vmax
          or
          (Decrease) Enzyme no longer saturated; or further from saturation;
  e. pH variation
     Change:                                 1 pt
          a) Slight change may affect the curve either way
          b) Drastic change may stop the reaction
     Explanation:                            1 pt
          a) Enzyme has optimum pH
          b) Enzyme can be denatured by extremes
                                        Maximum = 6 pts

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