rp11

Question 1

how to produce calibration curve for glucose

Answer 1

use distilled water and glucose solution of known conc
produce dilution series
heat set volume each solution with benedicts
measure absorbance using colorimeter
plot graph absorbance y
conc of glucose x
line best fit

Question 2

Describe how the concentration of glucose in an unknown ‘urine’ sample
can be identified using a calibration curve

Answer 2

Perform Benedict’s test on sample using same volumes of solutions used in producing calibration curve
Measure absorbance using a colorimeter
Absorbance value for ‘urine’ sample read off calibration curve to find associated glucose concentration

Question 3

Give examples of variables that should
be controlled.

Answer 3

volume of sample
temp of water bath
time of sample in water bath
volume of Benedict’s

Question 4

Explain why a high blood glucose
concentration can cause glucose to be
present in the urine of a diabetic person.

Answer 4

● Not all glucose reabsorbed at proximal convoluted tubule
● As glucose carrier / cotransporter proteins are saturated /
working at maximum rate