1. Liquid Waste Removal System Kidshealth video Video
The Excretory System
Liquid Waste Removal System
Kidshealth video
Video

2. The wastes would poison you if you didn’t get rid of them.
Excretion= the process by which the body collects and removes waste produced by cells.

3. Waste removal is done by the excretory system (Kidneys, ureters, bladder, and urethra
The organs that filter wastes from the blood
Mostly filters out Urea
Each kidney is about the size of a fist.

4. Blood reaches the kidneys through large blood vessels
The blood vessel then branches into smaller vessels and eventually into capillaries.
Each capillary forms a tight coil called a Nephron

5. The nephron is the filtering unit of the kidney
Each kidney contains over a million nephrons

7. Capillary Coil A Nephron is surrounded by a cuplike capsule
As blood flows through the cap. coil, some of the liquid part moves out of the cap. coil and into the capsule
The blood cells stay behind
The liquid part consists of water with materials dissolved in it.

8. The liquid contains urea and also contains substances that are not wastes, substances your body needs.
As the solution flows through a long, twisted tube, the body reabsorbs the “Good” materials, leaving urea and waste product in the tube.

9. Urine is left behind Composed of water, urea, and other wastes
The lower urinary tract
This carries the urine away from the kidney and out of the body.
This doesn’t filter the urine in any way

10. Ureter- carries urine away from the kidney
There is one ureter from each kidney that leads into the bladder

11. Bladder It is a muscular sac that stores urine
When the bladder is full, the muscles squeeze the urine down the urethra

12. Urethra
The tube which urine leaves the body.

13. Other excretory organs
Your lungs, skin, and liver all play a role in removing waste products from your body.
CO2 is a waste product, which is released by the lungs and blood
Perspiration
Sweat (water and dissolved waste materials)
These leave your body through your skin

14. Your liver chemically changes wastes, impurities, poisons, alcohol, and drugs to less harmful substances.
Some of these byproducts go through the kidneys and leave in the urine, others go into the small intestine and leaves with the feces.

15. Disorders of the Excretory System
Infections of the bladder and urethra
Most common excretory disorder
Symptoms= frequent urination, burning, painful feeling during urination.
These should be treated quickly
Infection could spread to the kidneys
Infections are the most common cause of nephritis
Inflammation, or swelling, of the nephrons

16. Kidney stones
Pebble like masses of salts in the kidneys or urinary tract.
Very painful when they get stuck in the urinary tract
Sometimes they can be passed, other times they need to be medically removed.
They can now be removed by an ultrasound machine

17. Uremia (yoo REE mee uh)
Poisoning of the body caused by the failure of the kidneys to remove waste from the bloodstream.
If it is due to a kidney infection, antibiotics can be used
If the kidneys stop working = kidney failure

18. Kidney failure Must undergo kidney dialysis
A machine is used to filter blood instead of the kidneys
This takes a couple of hours every week.
Blood is removed from the body and filtered in the machine

19. Keeping the Excretory system healthy
The waste products that are filtered by the kidneys are poisons.
Drink a lot of water to dilute these poisons. Try to drink 6-8 glasses of water a day.
If you are fighting off an infection or a fever, drink more water because your system is working even harder.