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Hidden Sugars in Food

Postby Krisshan74 » Mon Feb 12, 2018 7:51 am


I am working on the Hidden Sugars project for my science fair. I had a question on the -Testing Invertase Activity section.
My graph was not as linear as shown in the experiment. How do I determine the Linear Point? Is it safe to say 15 or should it be 30 as the Invertase activity has plateaued at this point. Please help.

Invertase activity.docx
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Re: Hidden Sugars in Food

Postby SciB » Thu Feb 15, 2018 8:41 pm

Hi Akki,

I looked at your graph and I think you did everything correctly. Some of the points (the 20 and 25 minute ones) are off the linear part of the curve but the trend seems clear. The change from linear to plateau is not going to be perfectly sharp. The straight line will gradually curve over until it reaches horizontal. I would estimate from your data that the time to plateau is 25 minutes. The time at half maximum rate, 1% glucose, would be 10 minutes.

Let us know if you have more questions.


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