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Q. In an investigation, a student wanted to identify the solutions is two beakers, A and B. She knew one beaker contained maltose solution and the other beaker contained glucose solution. Both solutions had the same concentration.
She did 2 separate biochemical tests on a sample from each beaker.

TEST 1- used benedicts solution to test for reducing sugar
TEST 2- added the enzyme maltase heated the mixture at 30 degrees
celc for 5 mins, and then used benedicts solution to test for
reducing sugar.

Results shown....
Test 1 Test 2
A red red
B red dark red

Explain the results for...
beaker A
beaker B
For Test 1, Benedict's solution showed a positive result for the reducing sugars Maltose and Glucose as expected, both with an equal and high concentration. Considering Test 2: Adding maltase to Beaker B broke down maltose into more glucose molecules (the moderate temperature allowing this to occur in a relatively short amount of time), since there are now more molecules/moles than we originally had (whilst the solvent remains the same) in Beaker B, the concentration has been increased and so Benedict's solution detected this larger concentration with more reduced Cu ions resulting in the darker colour. Maltase has no effect on Beaker A's glucose because of its tertiary structure and hence specific active site for maltose contrastingly explaining its repeated result between Test 1 and Test 2.
(This was,
1) Way too convoluted
2) Way too detailed
3) Wrong about Cu reduction?)
Original post by Sadjan_Stevens
For Test 1, Benedict's solution showed a positive result for the reducing sugars Maltose and Glucose as expected, both with an equal and high concentration. Considering Test 2: Adding maltase to Beaker B broke down maltose into more glucose molecules (the moderate temperature allowing this to occur in a relatively short amount of time), since there are now more molecules/moles than we originally had (whilst the solvent remains the same) in Beaker B, the concentration has been increased and so Benedict's solution detected this larger concentration with more reduced Cu ions resulting in the darker colour. Maltase has no effect on Beaker A's glucose because of its tertiary structure and hence specific active site for maltose contrastingly explaining its repeated result between Test 1 and Test 2.
(This was,
1) Way too convoluted
2) Way too detailed
3) Wrong about Cu reduction?)

Thank you ! it helped a lot !
Hi does anyone have the edexcel biologyAS papers 2020. Thanks

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