Final answer:
Nephrons are the functional units of the kidney responsible for filtration, reabsorption, secretion, and other secondary functions like blood pressure regulation, red blood cell production, and calcium absorption.
Step-by-step explanation:
The student asked about the functions of the nephron units of the kidneys that do not include. The nephrons are the functional units of the kidney that play a crucial role in filtering blood and forming urine. They carry out several essential functions, including filtration, reabsorption, and secretion.
Filtration occurs in the renal corpuscle, where blood pressure forces fluids and solutes out of the blood in the glomerulus into Bowman's capsule. Reabsorption takes place mainly in the proximal convoluted tubule, loop of Henle, and distal convoluted tubule, where useful substances are absorbed back into the blood. Secretion involves the selective addition of substances from the blood into the filtrate.
Secondary functions of the nephron include blood pressure regulation through renin production, stimulating red blood cell production via erythropoietin (EPO), and influencing calcium absorption by converting calcidiol into calcitriol. Thus, any option that does not involve these primary or secondary functions would be the correct answer.