From the equation, it can be concluded that one mole of glucose reacts with two moles Cu2+ to give one mole of Cu2O. Thus, one can weigh the mass of Cu2O formed and relate it to the amount of glucose present in a solution. This method can be used to study the rate of glucose uptake by yeast cells.
2. Start the timer and add 1.00 mL of yeast suspension with a micropipette into one flask containing the glucose solution. Repeat this until 7 replicates are obtained. Please note that this has to be done very fast (within 1 minute if possible). To the remaining flasks, add 1.00 mL of distilled water into each, and label them as blank.
4. After 30 minutes have elapsed, pour the contents of one flask labelled blank sample and one containing the yeast suspension into two separate beakers containing around 150 mL of boiling distilled water. Cool the mixtures to room temperature and transfer them into two separate 250-mL volumetric flasks. Add distilled water to the flasks to make a final volume of 250.00 mL. Shake the flasks well and let them stand until clear supernatants are obtained (the blank solution should not have a sediment if the experiment has been done properly). Label the one obtained from the blank sample as B60 and the other one as Y60
5. Pipette 25.00 mL of supernatant from B60 and pour it in a 100 mL beaker. ...Show more