What is glomerular filtration?

Glomerular filtration is the process where blood is filtered in the nephron, specifically at the glomerulus, a network of capillaries located at the beginning of the nephron. During this process, blood pressure forces water, electrolytes, and small molecules through the glomerular membrane while larger molecules and cells remain in the bloodstream. This initial filtration step is crucial for forming urine and regulating the composition of blood, as it effectively removes waste products and excess substances from the body.

The mechanism of glomerular filtration is essential for maintaining homeostasis, as it initiates the renal processes that will eventually lead to either reabsorption or excretion of various substances. Understanding glomerular filtration is a foundational aspect of studying how kidneys function and manage bodily fluids and waste.