In desert rodents, efficient reabsorption of essential solutes such as glucose from the glomerular filtrate is vital to prevent metabolic waste. Describe and explain three structural adaptations of epithelial cells lining the proximal convoluted tubule that facilitate the rapid selective reabsorption of glucose into the blood.

The drug Tolvaptan is a selective antagonist that blocks ADH (vasopressin) receptors, preventing the insertion of aquaporins. Name the two regions of the tubule system in a nephron where this drug directly prevents water reabsorption.

Aquaporins are highly selective, allowing only polar water molecules ($H_{2}O$) to pass through while completely blocking other small ions like protons ($H^{+}$). Suggest and explain how the structure of the aquaporin channel achieves this selectivity.

A patient suffering from head trauma experiences a condition where the secretion of ADH in response to high blood solute concentration (high plasma osmolarity) is severely impaired. State the precise location of the sensory receptors that normally detect an increase in blood solute concentration, and explain how this impairment in ADH release affects the solute concentration of both the patient's urine and their blood plasma.