UB BIO 201LLB - Lab3_

This preview shows page 1 out of 3 pages.

View full document
Premium Document
Do you want full access? Go Premium and unlock all 3 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

Table 1: Enter your Part 1 data from the dataset provided in UBlearns.Table 1. Part 1: Dilution seriesTube # dilution A4202 1/100x 1.293 1/1000x 0.274 1/10,000x 0.02Based on data and info in Lab 5 procedure, which dilution should be used for Part 2? 1/1000xTable 2: Enter your Part 2 data from the dataset provided. Enter formulas for average and standard deviation for each pH.Table 2. Part 2: pH dependence of LactasepH End-point Absorbance at 420 nm (A420)Trial 1 Trial 2 Trial 3 Mean Stdev2 0.09 0.10 0.08 0.09 0.01 Remember to enter formulas and cell references for all means and standard deviations.4 0.44 0.42 0.47 0.44 0.036 0.23 0.18 0.19 0.20 0.038 0.01 0.04 0.06 0.04 0.0310 0.01 0.00 0.02 0.01 0.01Graph: Use a line graph to plot mean end-point A420 vs. pH. Include error bars displaying standard deviations. Do not forget to label your axes.In the spaces below, calculate mean ONP concentration at the end-point of the reaction at your pH optimum for Lactase: To do this rearrange the Beer-Lambert equation (A = elc) to solve for c. In your formula, reference the cell in Table 2 that contains the mean A20 at the enzyme's optimal pH; o-Nitrophenolate extinction coefficient (e) = 4500 L/(mol cm), and path length = 1 cm.0.000099 M "Enter formula, not a raw number. (e.g. cell C1 times 32divided by 2 is ""=C1*32/2"")"98.5 µM Convert M to µM (enter formula using cell reference for the concentration in M above; Exponents in Excel are expressed using the ^ sign, e.g. 10 to the 4th power is 10^4.)Questions - Enter your answers into the spaces provided below1. Before this experiment began, what was your hypothesis as to the pH optimum of lactase? Remember that a hypothesis is a statement. (0.5 pt)the pH optimum of lactase is acidic.2. Was your hypothesis correct? Either way, explain. (0.5 pt)Based on the data, the optimum pH of lactase is 4 which means my hypothesis is correct. In addition, the lactase enzyme is located in the human small intensinewhich has acidic environment. 3. Why do you have to change pipets/tips between each solution, and what is the only time you DON'T have to change pipets/tips? We need to change pipets/tips between each solution in order to avoid contamination. We do not need to change pipets/tips when we pipet 9.0 ml enzyme solution into each of 4 test tubes because tubes are empty and they are unlikelyto contaminate the serological pipette.4. What do you have to do with your test tubes when you are finished with the lab? (1 pt) We need to make sure that we remove all tubes from the spectrophotometer and turn off power. All tubes that have been used must be emptied and rinsed using awash bottle and poured into a waste beaker. All rinsed and empty tubes should beplaced into a test tube bucket by the sink.Table 1 data (0.25 pts):Correct dilution to be used for Part 2 (0.25 pts):Table 2, incl. formulas, cell references (0.75 pts):Graph of Part 2 data (0.75 pts):ONP calculation (0.5 pts):Total for questions (1.5 pts):TOTAL (8 POINTS POSSIBLE):

View Full Document

UB BIO 201LLB - Lab3_

Download Lab3_
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...

Join to view Lab3_ and access 3M+ class-specific study document.

We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Lab3_ 2 2 and access 3M+ class-specific study document.


By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?