11. Each nephron begins with a secretion of wastes from the blood into the urine. 12. The mesonephros go on to form nephrons and other associated structures of the kidneys. 13. This can block the flow of urine causing the death of the respective nephrons . 14. Similar to mammalian species, the functional units of avian kidneys are the nephrons . 15. Birds have small glomeruli, but about twice as many nephrons as similarly sized mammals. 16. Vasopressin regulates the body's nephrons . 17. The trimethoprim portion acts to prevent potassium excretion in the distal tubule of the nephron . 18. Together they can form an insoluble precipitate which blocks the distal part of the nephrons . 19. Aldosterone receptors are present on the epithelial cells of the distal nephron in the kidney. 20. Within the cortex, nephrons are organized around central veins of the efferent venous system.
