Excretory system

Purpose The excretory systems purpose is to remove wastes from the body The wastes can be liquids, solids, or gases Other systems are involved

Urinary System The purpose of the urinary system is to remove wastes from the body in a liquid form called urine. The four major parts to the urinary system are the kidneys, ureters, bladder and urethra.

Kidneys Two bean shaped organs found at approximately waist level. The filtering unit of the kidney is known as the nephron. Each nephron has a cup-like structure called the Bowman’s capsule and a duct. The nephrons filter the blood for wastes

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The ureters Two relatively thin tubes that attach the kidneys to the bladder.

Bladder Muscular storage unit for holding urine until it is ready to be released. Can Hold about a half a liter of fluid

Urethra A single tube that flows from the bladder to the outside for the release of urine. Can become infected and inflamed with bacteria . Common beginning site for a urinary tract infection.

Diseases Some diseases of the urinary system are benign and just require antibiotics for treatment. You only require one kidney to work. If both kidneys fail then you need dialysis which is the artificial filtering of the blood for waste.

Skin The skin- responsible for sweating and the release of wastes

Skin Largest organ Made up of three layers Epidermis- outer most layer Made up of dead skin cells Acts an water repellant and first protection for your body Melanin- your skin pigment or color is produced here

Dermis and Fatty layer Dermis- middle layer Thicker than the epidermis Blood vessels, nerves, oil glands and sweat glands are found here Fatty layer- inner most layer Insulates the body

Skin functions Major job is protection Protects from physical and chemical injury Protects from bacteria Sensory response Sense of touch

Skin functions cont. Vitamin D production Helps absorb Calcium Regulates body temperature Rid the body of wastes In the process of sweating- the body is removing Water Salts Other waste products like carbon dioxide

Skin functions cont. Your body can only withstand a limited range of temperatures If body becomes too hot then you will sweat The sweat will evaporate and cool the body Regulates body temperature and wastes In the process of sweating- the body is removing Water Salts Other waste products like carbon dioxide

The digestive system Solid waste exits the rectum after the water has been reabsorbed in the large intestine

Lungs Lungs are part of the respiratory system and are responsible of the removal of carbon dioxide and some water.