Final answer:
The process where fluid moves out of blood from the arterial end of a capillary by bulk flow is called filtration, driven by capillary hydrostatic pressure which is higher than blood colloidal osmotic pressure. Large solutes are blocked during this process.
Step-by-step explanation:
The process that occurs on the arterial end of a capillary whereby fluid moves by bulk flow out of blood through the openings in capillaries is called filtration. In this process, large solutes are blocked. Filtration is driven by the capillary hydrostatic pressure (CHP), which is higher at the arterial end of the capillary, overcoming the blood colloidal osmotic pressure (BCOP) and forcing fluid and nutrients out of the capillaries into the surrounding tissues.
At the arterial end, the hydrostatic pressure difference between the capillary interior and the interstitial space pushes water and small solutes out of the capillary, while larger molecules like proteins are generally too large to pass through the capillary walls. This mechanism is essential in delivering nutrients to tissues and -removing waste products. Towards the venous end of the capillary, BCOP becomes greater than CHP, facilitating the net reabsorption of fluid into the capillaries.