In an experiment to test the activity of lactase under different conditions, tubes containing buffer, ONPG, and lactase were set up. Absorbance was recorded from the spectrophotometer. Select true or false for each of the statements regarding the lactase experiment below! v The absorbance will decrease at a constant rate as the amount of A. TRUE ONPG is increased. B. FALSE v As pH increases above 1, there would be an initial increase in intensity of yellow color which then plateaus. v Greater amount of lactase is released when experiment is performed at 37°C than at 100°C. v Adding increasing amount of lactose would cause the absorbance to decrease.

1. Start with the Michaelis-Menten equation and convert it to a double-reciprocal equation. Show how you would make a linear Lineweaver-Burk plot using this equation. 2. Based on th chart make a Lineweaver-Burk plot and later use the plot to complete the information in the table.

A research group discovers a new version of happyase, that catalyzes the chemical reaction HAPPY = SAD. The reseachers begin to characterize the enzyme. In the first experiment, with [E] at 4 nM, they find that the Vmax is 1.6 µM/s. Based on this experiment, what is the kcat for happyase? 1/s

1) Which statement about the electric organ is FALSE? A) the electric eel has postively charged cells on one of its body and negatively charged cells on the other B) the electric organ consists of a stack of cells with Na+ channels on one side C) an electric eel can maximize the shock delivered to a prey animal by contacting it with both ends of its body D) in the electric organ positive ions diffusing into the cells make the surrounding membrane positive 2) Which of the following sensory systems does NOT use hair cells with kinocilia and stereocilia that have ion channels at their bases? A) lateral line system B) vestibular apparatus C) hearing D) All of these sensory systems utilize hair cells with kinocilia and stereocilia.

A researcher wants to look for glucaronic acid conjugated metabolites in sample of urine(glucaronic acid conjugation is a common method of metabolism for excretion.) Pronotated glucaronic acid conjugated metabolite ions often lose anhydroglucaronic acid(176 Da) during low energy CID. Which triple quadrupole experiment might be best for finding these conjugates?

Sucrose + H2O(negative control): Colorless to brown solution: Blue solution Conclusion for Iodine test A. amylose present B. amylose not present Conclusion for Benedict's test A. reducing sugars not present  B. reducing sugars present  Sucrose + HCl(potential hydrolysis): unchanged compared to sucrose+water:  Conclusion for Iodine test A. more amylose present B.  LESS amylose present C. NO change  Conclusion for Benedict's test a. more reducing sugar present  b. less reducing sugar present   c. no change  Did hydrolysis of sucrose occur in the presence of acid? A. Yes  B. no

Table 1 - Comparison of the effect of catechol concentration on the amount of product formed. Absorbance Potato extract Absorbance 0 mins after 30mins (2nd reading) (mL) 1st reading 1 Tube # la blank 2a 3a 4a 1 1 1 dH₂O Catechol (mL) (mL) 7 5 3 1 0 2 4 6 0.00 0.060 0.033 0-05-2 Q4) Give 2 reasons for adding dH₂O to these tubes in Table 1? Time for reading: 3:21 -0.11 Absorbance: Time for reading: 3.36 Q5) Tube la serves as a control, but why is this control needed? Absorbance: 0.197 Time for reading: 3.37 Based on the data from Table 1 answer these questions: Q1) What is the name of the enzyme found in potato extract? Answer: catechol Q2) What is the substrate? Answer: THO Q3) Name of product of this enzyme catalyzed reaction? Answer: Absorbance: 0.152 Time for reading: 3:39 Absorbance: . 166 ness Catechol Benzoquinone Subtract 1st from 2nd reading -0.01 0-137 0.11.19 0.119 Q6) Notice that your 1st absorbance reading in tubes 2a-4a are quite similar but it then becomes very different…

a quinine tablet is taken to prevent malaria, t days later, 50(0.23)^t mg remain in the body.  A. How much quinine is in the tablet? At what rate is it decaying?    B. How much quinine remains 12 hours after tablet is taken?

The enzyme phospholipase A2 has an optimal pH of 5.5. If a biochemist wants to set up an in vitro assay to screen inhibitors of this enzyme, which buffer system would be BEST?

You are given the task of determining the approximate % solute of potato cells. You decide to set up a series of 10 cups ranging from dH2O to 1% sucrose solution. You intend to drop a potato stick in each cup. a. What data will you collect for each potato stick? b.  In how many of the solutions will the potato sticks remain unchanged? c.