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A2 Biology Cousework...help needed plz

For my biology courseowork, i am investing the polyphenol oxidase activity of banana as it ripens.....i'm doing this by adding 0.1cm3 of enzyme extract into 2cm3 catechol and 2cm3 ph 7 buffer and taking readings at every 30 second intervals....i hv been going this for 3 days now on yellow bananas as my trial work and there's not much of a change in absorbance i.e its like 0.29,0.28 0.26... and the absorbance is going down...........what am i meant to do now?i.e start my original cousework with green bananas and just note down results that are similar to this........?

really need helppp
annsue
For my biology courseowork, i am investing the polyphenol oxidase activity of banana as it ripens.....i'm doing this by adding 0.1cm3 of enzyme extract into 2cm3 catechol and 2cm3 ph 7 buffer and taking readings at every 30 second intervals....i hv been going this for 3 days now on yellow bananas as my trial work and there's not much of a change in absorbance i.e its like 0.29,0.28 0.26... and the absorbance is going down...........what am i meant to do now?i.e start my original cousework with green bananas and just note down results that are similar to this........?

really need helppp


I could't tell you why, but your results seem right. As time goes on,, bla bla bla, the reabsorbance rate gets less because the ezymes are being used or the catechol has been used up extra. So even though they may appear wrong, stick with, it.

And yes, maybe it would be a good idea do another banana, green or not, to compare results

Regards

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Reply 2
MrBlackwood
I could't tell you why, but your results seem right. As time goes on,, bla bla bla, the reabsorbance rate gets less because the ezymes are being used or the catechol has been used up extra. So even though they may appear wrong, stick with, it.

And yes, maybe it would be a good idea do another banana, green or not, to compare results

Regards

Quote for reply



Do you know the role of ph7 buffer in my experiment....if so then can you please explain it to me coz i really do not get it
Reply 3
The pH could change over time.
This could effect the reaction speed and this your results.
A buffer is used to stop the pH changing.
annsue
Do you know the role of ph7 buffer in my experiment....if so then can you please explain it to me coz i really do not get it


A buffer solution keeps the solution at a constant pH
Reply 5
Original post by MrBlackwood
A buffer solution keeps the solution at a constant pH

Hi, I'm measuring the absorbance of benzoquinone in the presence of acidulants, but i used a pH buffer. i have a feeling i've don e my investigation wrong.:frown:

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