Download Excretory

Excretory System
Removes wastes from the body.
Excretion: The process of removing wastes
and excess products from the body.
Three systems are involved in excretion:
1. Respiratory – Lungs remove carbon dioxide.
2. Integumentary – Skin removes waste and
water when you sweat.
3. Urinary – Kidneys remove wastes from blood.
Urinary System
Removes waste products from the blood.
Urinary system is made up of:
• Kidneys
• Ureter
• Bladder
• Urethra
Kidneys
• Two kidneys constantly clean the blood
• Nephrons are found inside the kidneys.
• Nephrons are filters that remove harmful
substances from the body.
• Urea is one of the most important wastes
removed from the body.
• Urea is produced when proteins are used for
energy.
How Kidneys Filter Blood
1. Blood is brought to each kidney by an artery.
2. Smaller blood vessels take blood to nephrons.
3. Water and other substances are forced out of
blood vessels and into the nephrons.
4. Most of the water and some nutrients are returned
to the blood vessels after traveling through
the nephrons.
5. The cleaned blood leaves each kidney through a
vein.
Waste Removal
6. A concentrated mixture of waste materials, urine,
is left behind in the nephrons.
7. The urine leaves each kidney through a slender
tube, ureter, that takes it to the urinary bladder.
8. Urine is stored in the urinary bladder.
9. Urine leaves the body through another tube called
the urethra.
Urination is the process of expelling (removing) urine
from the body.
Vein
Artery
Kidney
Ureter
Bladder
Muscle
Urethra