Anatomy and Physiology II Practice Test

Is glucose typically found in normal urine?

1. Yes, in high amounts

2. Yes, in low amounts

3. No, it is normally reabsorbed

4. No, it is always secreted

The correct answer is: No, it is normally reabsorbed

Glucose is usually reabsorbed in the kidneys during the filtration process. Under normal physiological conditions, the kidneys filter blood, allowing substances such as glucose to pass through the glomerulus. However, in healthy individuals, the renal tubules, particularly in the proximal convoluted tubule, resorb nearly all the filtered glucose back into the bloodstream. The presence of glucose in urine is an indication of high blood sugar levels that exceed the renal threshold for glucose reabsorption, which is why glucose is typically absent in normal urine. When blood glucose levels are too high, the kidneys cannot reabsorb all the glucose, leading it to appear in the urine as "glycosuria." This explains why the option stating that glucose is normally reabsorbed is the accurate choice, reflecting the expected physiology of glucose handling in the renal system.