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- 2006
Greetings, fellow Biology students or former students....
The experiment we did at school on factors affecting enzyme activity was sooo effed up....so basically, I'll be screwed if a question in the HSC comes up about this experiment. I need some help. The enzyme we used was amylase (substrate = starch) and here's a brief outline of what we did:
Temperature:
We had three test tubes of enzyme and substrate. One was placed in a warm water bath at optimum temp, one in an ice bath and another in a hot water bath. Iodine was used to indicate whether enzyme activity has occurred. The result was that the iodine decolourised quickly and completely in the solution in the hot water bath, barely decolourised in the solution in the warm water bath and did not decolourise at all in the ice bath. The iodine was supposed to decolourise rapidly at optimum temp. For the hot water bath, the iodine was supposed to decolourise to a point where the enzyme denatured. For the ice bath, there was meant to be no decolourisation. So, the only one that worked out as expected was the one in the ice bath.
Substrate Concentration:
We had three test tubes of enzyme. One had a high concentration (given conc of starch was 1.5% which not paritcularly high), one had a medium concenration (dunno numerical values just added water thanks to great group work lol) and one had a low concentration (dunno numerical values just added lots of water thanks to great group work lol). Again, iodine was added as an indicator. The result was that as concentration increased, there was decrease in enzyme activity which was what we expected.
pH:
Now this is the bit where its totally f***** up. We didn't have time to do the pH experiment and instead, we got some worksheet that covers it. However, there's one problem. The worksheet described the test for catalase instead of amylase which is a totally different test!!!!!!!!!!!!!!!!!......and I don't know how the experiment for pH changes in amylase goes.........so I'm lost here......
My questions are:
- In an exam question that regards this experiment, do we list the expected results or actual results?
- In an exam situation, what the hell do I do with the pH part since we didn't do it at all and got a worksheet that uses a totally different enzyme and substrate?
It would be great if you could help me out here......thanks.........
The experiment we did at school on factors affecting enzyme activity was sooo effed up....so basically, I'll be screwed if a question in the HSC comes up about this experiment. I need some help. The enzyme we used was amylase (substrate = starch) and here's a brief outline of what we did:
Temperature:
We had three test tubes of enzyme and substrate. One was placed in a warm water bath at optimum temp, one in an ice bath and another in a hot water bath. Iodine was used to indicate whether enzyme activity has occurred. The result was that the iodine decolourised quickly and completely in the solution in the hot water bath, barely decolourised in the solution in the warm water bath and did not decolourise at all in the ice bath. The iodine was supposed to decolourise rapidly at optimum temp. For the hot water bath, the iodine was supposed to decolourise to a point where the enzyme denatured. For the ice bath, there was meant to be no decolourisation. So, the only one that worked out as expected was the one in the ice bath.
Substrate Concentration:
We had three test tubes of enzyme. One had a high concentration (given conc of starch was 1.5% which not paritcularly high), one had a medium concenration (dunno numerical values just added water thanks to great group work lol) and one had a low concentration (dunno numerical values just added lots of water thanks to great group work lol). Again, iodine was added as an indicator. The result was that as concentration increased, there was decrease in enzyme activity which was what we expected.
pH:
Now this is the bit where its totally f***** up. We didn't have time to do the pH experiment and instead, we got some worksheet that covers it. However, there's one problem. The worksheet described the test for catalase instead of amylase which is a totally different test!!!!!!!!!!!!!!!!!......and I don't know how the experiment for pH changes in amylase goes.........so I'm lost here......
My questions are:
- In an exam question that regards this experiment, do we list the expected results or actual results?
- In an exam situation, what the hell do I do with the pH part since we didn't do it at all and got a worksheet that uses a totally different enzyme and substrate?
It would be great if you could help me out here......thanks.........
