URINARY SYSTEM. (HOW URINE MOVES OUTSIDE)

The urinary system consists of kidneys, bladder and tubes. This system acts as a filtering mechanism for the blood. Kidneys, bladder and tubes regularly control the amount of water and salts that are absorbed back into the blood and also what is taken out as waste.

Our body takes nutrients from food and uses them to maintain all functions of human body including energy and self repair. When our body gets what it needs from the food, waste elements are left behind in the blood and bowel. The urinary system removes a type of waste called urea our blood. Urea is produced when foods containing protein and different vegetables are broken down in the body. Urea reaches in the bloodstream to the kidneys.

Kidneys are found near the middle of the back. These are bean shaped organs. The size of kidney is like human fist. There many tiny filtering units in the kidneys called nephrons. The kidney remove urea from the blood through nephrons. There is found small capillaries in the nephron. These capillaries called glomerulus. Another small tube called renal tubule is found in the nephron. Urea, water and other substances forms the urine as it passes through the nephrons and down the renal tubules. Urine travels to the bladder through two thin tubes which are 8 to 10 inches long. These tubes are called ureters. Walls muscles in the ureters continuously force urine outside from the kidneys. Approximately from 10 to 15 seconds small amounts of urine are emptied into bladder from the ureters. The bladder is a shaped like a balloon. The bladder is found in our pelvis and is held in place by ligaments attached to other organs.          If someone tries to keep store urine, a kidney infection can develop. When a normal quantity of urine reaches in bladder, then we go to washroom to empty the bladder. When it is full of urine then it swells into a round shape and gets smaller when empty. The bladder can hold up to 2 cups of urine for to 2 to 5 hours in a healthy urinary system.  There are circular muscles that help keep urine from leaking. This circular muscles are called Sphincters. These sphincter muscles close tightly around the opening of the bladder in to tube (urethra) that allows urine to send outside the body.

As the bladder first fills with urine, you feel that you need to urinate. The sensation to urinate becomes stronger as the bladder fills more and reaches its last limit. When bladder becomes full then nerves from the bladder send message to the brain to empty the bladder. When you go to urinate, your brain order bladder muscles to tighten and at the same time, the brain signals the sphincter muscles to relax. At this time the urine exits the bladder. Normal urination occurs when all the signals occur correctly.