{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Wheat Germ Acid Phosphatase - The Affects of Varying...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
4-1-05 The Affects of Varying Conditions on the Enzyme Wheat Germ Acid Phosphatase Objectives : Enzymes are important for nearly all functions in the cells of both plants and animals. Reactions that normally would take hours or days can be catalyzed by an enzyme to happen in a few seconds. To determine the rate of reaction one would measure the amount of substrate used or product generated over time. The rate of reaction which we determine can be varied by changing the reaction conditions. The reaction conditions we varied were time, temperature, substrate concentration, and enzyme concentration. To gauge the reaction progress, we used a substance called PNPP in which the absorbance changes as the product of the reaction is formed. I. Time Course Data of Absorbance for Each Time Assay with Calculation of Micromoles Tube Absorbance Micro Moles 0 0 0 2 0.501 111.3 4 0.798 177.3 6 1.123 249.5 8 1.384 307.5 10 1.604 356.4 12 1.86 413.3 The tube column has values for how many minutes the reaction was allowed to progress. The absorbance column was data taken directly from the spectrophotometer after using the blank (zero tube). The last column was calculated using a given formula with the extinction coefficient (18.8x10^3 liter mol^-1 cm^-1). 1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
4-1-05 Reaction Progression of Above Data Plotted on a Graph Micromoles vs. Time y = 66.439x - 35 0 50 100 150 200 250 300 350 400 450 500 0 2 4 6 8 10 12 Time Micro Moles of p-nitrophenol This graph shows a plot of micromoles p-nitrophenol versus reaction time. The data points are the blue rectangulars and the blue line connecting them shows a slight trend. The red line is the actual trend line. The equation for that trend line is also given. A.) Is the time course linear throughout? If the time course is not linear, what are some factors that might contribute to the changed velocity at longer periods of time? B.) Is the 5-minute fixed-time assay valid for acid phosphatase? If not, how should it be changed? C.) Determine the slope of the graph . Our plot for the data collected yields a fairly straight line with a slight curve at the beginning and towards the end. The reason for the curve is that at around 9-10 minutes of reaction time, all of the substrate is being used up. This will cause a leveling out of the reaction progress, because after the substrate is consumed, the enzyme has no materials with which to make its products. The twelve minute assay we performed was a decent amount of time to get an accurate picture of how the reaction will plateau. If we had used a five minute assay, we would conclude from our data that this reaction would continue 2
Background image of page 2
4-1-05 forever if we allowed.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}