Urinary SystemAKA Excretory System

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The function of the excretory system is to maintain homeostasis by filtration and absorption. The system removes liquid wastes from your blood and releases them to the outside world.

Kidneys

The bean-shaped kidneys, one on each side of the backbone, filter blood to get rid of waste in the body. These wastes could poison you. Waste is turned into urine inside of the kidneys.

Urine

Once blood enters the kidneys, the waste from blood is filtered out. Urine remains. Urine is formed by water, salt, and urea, a waste product of broken down proteins. If you urinate, your pee may vary in color. Dark yellow urine means there is a lot of urea in your system. Lighter urine means you have excess water in your body.

Ureters

Ureters leave from the kidney and push the urine to the bladder. Ureters are like subways that connect two destinations. The urine's last stop is in the bladder.

Bladder

The bladder is similar to a balloon that holds your urine. When urine comes in, the bladder expands like a pouch. It can hold about 16 ounces of liquid. When the bladder is full, you feel the need to urinate.

Urethra

Urine exits your body through a tube called the urethra. While males and females have different ways that the urethra looks, they both serve the same purpose- release the toxins!

Sphincter Muscle

The bladder doesn't hold the urine on its own. The sphincter muscles at the bottom of the urethra squeeze shut while the bladder is filling up. The nerves in your sphincter send messages to your brain that signal when you can't hold it any longer. The sphincter muscles relax when you urinate.

Practice questions

1) What is the correct pathway for urine?◦a) urethrabladderureterkidney◦b) ureterkidneybladderurethra◦c) kidneyureterbladderurethra◦d) bladder urethra kidneyureter

Practice questions

1) What is the correct pathway for urine?◦a) urethrabladderureterkidney◦b) ureterkidneybladderurethra◦c) kidneyureterbladderurethra◦d) bladder urethra kidneyureter

Practice Question

2) What is the purpose of the urinary system?

Practice Question

2) What is the purpose of the urinary system?To remove liquid waste from your body.