Students performed an investigation simulating diagnostic tests on urine. They were given three synthetic urine samples, labeled P, Q, and R, which corresponded to:
The table below shows the results of their tests:
| Sample | Glucose test | Protein test |
|---|---|---|
| P | positive | negative |
| Q | negative | positive |
| R | negative | negative |
(i) Identify which sample represents a healthy individual. Use your biological knowledge of ultrafiltration and selective reabsorption to explain why healthy urine does not contain glucose or protein.
(ii) Identify and explain which sample is from the individual with high blood pressure.
(iii) Describe the chemical test used to confirm the presence of protein in a sample.
Suggest a safety reason why synthetic urine samples are preferred over genuine human urine samples in school biology laboratories.
