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Sucrose, Fructose, and Glucose Project Question

Postby AnalyVega13 » Sat Jan 02, 2021 7:58 pm

Good Afternoon,
I have been working on this project, and as I was working on the "Testing Invertase Activity" I realized that all my results remained at a plateau. The color in the glucose strip test remained the same for every time interval that I checked. Could this be because I prepared both the sucrose mix and the invertase a day before?

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Re: Sucrose, Fructose, and Glucose Project Question

Postby MrsRondez » Mon Jan 04, 2021 10:32 am


Yes, as it states in the experiment procedures, "When invertase is added to the sucrose solution, the concentration of glucose should increase over time as the sucrose is converted to glucose. However, after some amount of time, the concentration of glucose will appear to remain the same, or plateau."

The way to do this experiment so that you do not just get the same glucose reading is to observe as soon as you mix the solution. Step 2 in the procedures explains how to do this:

"In your lab notebook, make a table for recording your data. You will be taking glucose readings over time to see how much sucrose has been converted to glucose by the invertase enzyme.
Starting at zero, plan on taking glucose readings every 5 minutes for the first 30 minutes, and then every 10 minutes after that. Plan on taking readings for 90 minutes total."

The same glucose readings occurs after a certain amount of time because, "Although the invertase may still be converting sucrose to glucose, it is doing it at an extremely reduced rate. This is probably partly due to product inhibition, which is when the product of a reaction (glucose in this case) stops the enzyme (invertase) from making more product."

Let us know if you need more assistance!

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