ANATOMY

Detailed explanation-1: -The process by which glomerular filtration occurs is called renal ultrafiltration. The force of hydrostatic pressure in the glomerulus (the force of pressure exerted from the pressure of the blood vessel itself) is the driving force that pushes filtrate out of the capillaries and into the slits in the nephron.

Detailed explanation-2: -Hydrostatic pressure within the glomerular capillaries promotes or enhances filtration. The other two forces oppose filtration and are: back pressure from hydrostatic pressure of the fluid within the capsule and colloid osmotic pressure caused by the plasma proteins within the glomerular capillaries.

Detailed explanation-3: -The rate at which kidneys filter blood is called the glomerular filtration rate. The main driving force for the filtering process, or outward pressure is the blood pressure as it enters the glomerulus.

Detailed explanation-4: -Filtration is primarily driven by hydraulic pressure (blood pressure) in the capillaries of the glomerulus. Note that the kidneys filter much more fluid than the amount of urine that is actually excreted (about 1.5 liters per day).

Detailed explanation-5: -The force of hydrostatic pressure means that as blood moves along the capillary, fluid moves out through its pores and into the interstitial space. This movement means that the pressure exerted by the blood will become lower, as the blood moves along the capillary, from the arterial to the venous end.