How do the kidneys work?
Answer
The kidneys sit posteriorly but right around the belly button. They're about the size of a fist and there are two of them. The kidneys receive blood from the heart, and the heart pumps blood throughout your body. There is some blood from the heart that goes to the kidneys. Both of the kidneys are going to filter the blood and release urine, which is a collection of waste products that sits in you bladder. Each kidney has an artery that goes to them. Arteries hold onto all the things in your blood. This includes nutrients like electrolytes, proteins, and glucose. Oxygen is also in your arteries; waste products like urea need to get rid of; too much sodium may all be part of your artery. The job of the kidneys is to make the nutrients you have in your arterial blood be collected and maintained when it gets over to the vein. The oxygen will go through the kidneys. A small amount of it will make it out to the vein side; some of it will be used by the kidney tissues. That's how to maintain the kidney tissue. The kidney wants to take all of the waste products and hold onto them. By collecting these waste products, the kidneys will effectively produce urine. How is it that the kidneys are able to help us maintain the nutrients in the body while getting rid of waste? The kidneys are special because it has two capillary beds. These capillaries work together taking the oxygen to the tissues and at the same time recollecting the nutrients so that the vein can take these nutrients elsewhere in the body for use. These capillary beds are called the vasa recta they're just to give oxygen to the kidneys. The second set are called peritubular capillaries. The peritubular capillaries are the ones responsible for collecting nutrients that the kidneys will filter.
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