homeostasis + kidney function

HOMEOSTASIS IS THE MAINTENANCE OF  A CONSTANT INTERNAL ENVIRONMENT

• body temperature (enzymes)
• water content (kidney, can damage cells)
• ion content (kidney, can damage cells)
• blood sugar (insulin ---> glycogen)
• carbon dioxide (lungs, is toxic)
• amino acids (urea, toxic)

thermoregulatory cente in brain controlles body temp.

internal temp = 37 

hot

• hairs = flat
• sweat from glands (evaporates to  remove heat)
• blood vessels dialate (heat transferres to air)

cold

• hairs stand up (trap insulating air)
• no sweat
• blood vessis constrict 
• shiver (needs respiration= releases energy = warm)

kidneys are filters

• remove urea (produced as waste in liver from reaction to get rid of excess amino acids)
• ajust blood ion content
• ajust blood water content

ions

• from food
• …