Final answer:
Glomerular filtration begins as blood enters the glomerulus under high pressure in a process called filtration, which doesn't require energy but relies on the pressure differentials to push solutes through a membrane.
Step-by-step explanation:
Glomerular filtration begins as blood enters the glomerulus under a high-pressure process known as filtration. This process filters out most solutes due to the high blood pressure exerted by the fluid against the capillary walls, which makes solutes pass through the 'leaky' connections between endothelial cells and specialized membranes into Bowman's capsule. The glomerular filtration rate (GFR) is a crucial indicator of kidney function, reflecting the volume of filtrate formed per minute by the kidneys.
Unlike processes that require energy, such as active transport, or rely on the concentration gradient, such as diffusion, and solvent movement across a semipermeable membrane as in osmosis, filtration is driven purely by pressure differentials across the glomerular capillaries.