The Physiology of the Urinary System

As we discussed previously, water, waste, and in fact virtually everything other than red and white blood cells are pulled out of the blood in the balled mass of arterioles known as the glomerulus, located at the front end of the nephron. All of this "waste" material then passes into the renal tubule portion of the nephron for "fine tuning." Keep in mind, that at this point, what we're referring to as waste contains virtually everything including the kitchen sink. If your body could not reclaim most of these elements, since many are essential for life, you would quickly die. That's why that as this pre-urine makes its way through the tubules of the nephron, it is fine tuned, with a bunch of things, including the water, that were previously extracted being put back into the bloodstream, as required by your body. In addition, some other things, such as medications, are pulled out in the tubules, as they are determined to be unnecessary during the process of fine tuning.To summarize: The primary purpose of kidney filtration is to balance out bio-chemicals in the bloodstream -- to achieve homeostasis. Excretion of toxins is a byproduct of this function. The stages involved in the process are glomerular filtration, tubular reabsorption, and tubular secretion. Let's now explore these elements in detail.

http://www.jonbarron.org/natural-health/physiology-urinary-system-what-causes-kidney-stones?utm_source=iContact&utm_medium=email&utm_campaign=Jon%20Barron&utm_content=Biweekly+Newsletter+3%2F26%2F12