Science18

10/1/09 Excretion System

Excretion:The removal of wastes from a living thing.

Wastes produced in our body:carbon dioxide,inorganic salts,heat,water,nitrogen

Organs of the Excretory System:Lungs,Kidneys,Liver,Skin


 * /24/09_Nervous System

Central Nervous System


 * Brain-gets and sends signals around the body;Major control center of body
 * Spinal Cord-is protected by spine;connects the brain to the rest of the nervous system

Peripheral Nervous System


 * Nerves-Travel through body;connect the spinal cord to sensors throughout the body

Voluntary Actions


 * Things you think about doing---juggling,walking,reading,bike riding

Autonomic (Involuntary Actions)

Things that you don't think about doing---breathing,response to danger,blinking

Brain


 * Most important part of our body
 * Protected by skull and three layers of tissue

Cerebrum

Right side of brain controls left side of body;Left side of brain controls right side of body
 * two haves--Right side is creativity, music,art,Left side is math,logic,speech,writing

Cerebellum

Muscle Coordination
 * Balance