Which procedure involves mechanical circulation of blood through semipermeable membranes?

The procedure that involves the mechanical circulation of blood through semipermeable membranes is hemodialysis. This medical treatment is primarily used for patients with kidney failure, functioning to remove waste products, excess fluids, and electrolytes from the blood when the kidneys can no longer perform these functions adequately.

During hemodialysis, blood is passed through a dialysis machine, which contains a semipermeable membrane that allows small molecules, like urea and creatinine, to pass through while retaining larger components, such as blood cells and proteins. The movement of substances across the membrane occurs via diffusion and osmosis, effectively cleansing the blood of toxins.

The other procedures listed involve different processes. Hematopoiesis refers to the formation of blood cells in the bone marrow. Hemorrhage is the excessive bleeding that occurs due to injury or medical conditions. Hemolysis is the destruction of red blood cells, which can release hemoglobin into the bloodstream but does not involve the mechanical removal of waste products from blood. These distinctions clarify why hemodialysis is the correct choice as it specifically describes the mechanical purification of blood through membranes.