EXCRETION 407 



4. Skin. 



Removes water, salts, etc. (Not primarily excretory.) 

 Structure. 



Epidermis, scale-like cells, loose. 



Protective, callouses. 



Modified as hair, nails, claws, horns, etc. 

 Dermis, fibrous cells. 



Many blood and lymph capillaries. 



Nerves, sweat and oil glands. 

 Functions. 



Protection from germs. 



Protection from injury. 



Protection from drying of tissues. 



Protection from water. 



Sensation. 



Excretion. 



Temperature regulation. 



Sweat excreted. 



Evaporated by body heat. 



Body therefore cooled. 



