Excretory+System

**__The Excretory System__**
__**Analyzing urine for sign of disease**__ __**Excretion and Homeostasis**__
 * As your cells use nutrients during many processes (and absorb many nutrients through many processes) they end up creating waste.**
 * At first waste won't do almost any harm, but after some time it can make you sick. To avoid this from happening our body has an excretory system, which contains different organs with the objective of taking that waste out of the body through a complex but simple method.**
 * In the Excretory System we have many different organs involved, some that even have jobs in other systems, like for example the lungs, in which through exhaling you release CO ² and some water.**
 * The most known and one of the most important processes happens in the lower part of our body, involving the kidneys, ureters, the urinary bladder and other organs. In this process the blood flows through ateries into the kidneys, where capillaries surround __nephrons__ (tiny filtration chambers) and leaves some water, urea, and sugar. After the sugar and some of the water is reabsorbed, while the rest goes to another tube (ureter). After it is stored in the bladder, it is released into the urethra and out of the body.**
 * When people go to a doctor for a checkup, they usually have their urine analyzed. A chemical analysis of the urine can be useful to detect diseases. Usually the urine has almost no protein or glucose. if glucose or protein is present in the urine, it might be a sign that you are having ptoblems with your kidneys, and that disease is called diabetes.**
 * Proteins and blood cells are too large to cross the nephron/capillary walls. Their presence in urine indicates some kind of problem in these tiny filtration units.**
 * Excretion mantains homeostasis by keeping the body's internal environment stable and free of harmful levels of chemicals. in addition to the kidneys, organs of excretion that mantain homeostasis include lungs, skin and liver.**
 * The __kidneys__ filter the blood and also regulates the amount of water in the body.**
 * The __lungs__ are able to remove CO² from your blood**
 * The skin can also remove some water and urea.**
 * The urea which comes from the break down of proteins comes from the __liver.__ The liver also uses old red blood cells to make bile.[[image:ewwwe.jpg width="435" height="398"]]**