What accept the reabsorbed substances and return then to the general circulation?

The kidneys are responsible for reabsorbing substances from the filtrate and returning them to the general circulation. Specifically, the renal tubules, particularly the proximal convoluted tubule, reabsorb essential nutrients, electrolytes, and water. This process helps maintain homeostasis by regulating the body's fluid and electrolyte balance. The reabsorbed substances then enter the bloodstream via peritubular capillaries.