Final answer:
The notion that very little glucose is reabsorbed from the tubular fluid is false; typically, nearly all glucose is reabsorbed in the PCT of the nephron.
Step-by-step explanation:
The statement that very little glucose is reabsorbed from the tubular fluid and is therefore lost in the urine is false. In the proximal convoluted tubule (PCT) of the nephron, almost 100 percent of glucose is normally reabsorbed and returned to the circulation. A phenomenon known as the transport maximum (Tm) exists, wherein the glucose transporters in the PCT can become saturated if blood glucose levels are exceedingly high, exceeding their capacity to reabsorb glucose, resulting in glucose loss in the urine. However, this typically occurs only in high-glucose scenarios such as hyperglycemia or diabetes mellitus, not under normal physiological conditions.