Human Excretory System Topic 16 Excretion The process

Human Excretory System Topic 16

Excretion The process of removing metabolic wastes Urea Metabolic waste formed by deamination of proteins (breaking down amino acids) in the liver

The KIDNEYS Filter wastes from the blood Nephrons make urine from wastes Fun Fact: Each kidney has about 1. 25 million nephrons! Image: http: //www. nlm. nih. gov/medlineplus/ency/imagepages/1101. htm

The KIDNEYS Substances needed by body are reabsorbed and return to the blood (water by osmosis, other materials by active transport!) Salts, urea & excess water form Urine Fun Fact: about 99% of water is reabsorbed!

How Kidneys Work • http: //www. youtube. com/watch? v=Tzw Pmz 5 V 6 Xg Image: http: //bryanking. net/disorders-of-the-kidney/

The URINARY SYSTEM • Urine formed in Kidneys • Ureters- bring urine to the urinary bladder • Urinary Bladder- stores urine • Urethra- tube which carries urine out of the body

Image: http: //kidney. niddk. nih. gov/kudiseases/pubs/yoururinary/

Malfunctions of the Excretory System Kidney Stones: High levels of Uric Acid & calcium crystallize Very painful Must pass stones or have them removed Image: http: //www. symptoms-kidney-stones-treatments. com/kidney-stone-surgery. html

Kidney Stone in X-Ray Image Courtesy of B. Beck

Organs of the Human Excretory System 1. Lungs �CO 2 & Water from Cellular Respiration 2. Liver �Deamination- break down proteins 3. Kidneys �Water, Salts, Urea 4. Skin �Water, Salts, Urea

The SKIN

The SKIN • Sweating cools the body • Sweat excretes water, salts & urea • Maintains HOMEOSTASIS Images: Microsoft Clip Art

• Brain Pop: http: //www. brainpop. com/health/bodysyste ms/urinarysystem/