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BIOLOGY FOR BEGINNERS 



Tongue. 



Structure, size, position in mouth. 

 Functions. 



1. Taste (what use for taste, where located). 



2. Aid in chewing. Aid in swallowing. 



3. Cleaning teeth. 



4. Speech. 

 Teeth. 



; Parts. Crown, neck, root (make diagram). 

 Structure. 



1. Enamel (structure and function). 



2. Dentine (structure and function). 



3. Pulp region, nerves, and blood supply (why each). 

 Kinds: 



Why two sets of teeth? 



How does the change take place? 



Special tooth adaptations in other animals, 

 Glands in general. 



Definition. 



Parts, secreting cells and ducts, blood and nerve supply. 



Various degrees of complexity. 

 Salivary glands. 



1. Parotid (where located, duct opening), mumps. 



2. Sub-maxillary. 



3. Sub-lingual. 

 Saliva. 



Composition, alkaline, watery, three pints daily, ptyalin. 

 Functions. 



1. Aids in tasting food (solution). 



2. Aids in swallowing. 



3. Stimulates gastric glands (alkali vs. acid). 



4. Ptyalin acts on starches slightly. 

 Digestive changes in the mouth. 



1. Food mechanically crushed. 



2. Moistened for taste and swallowing. 



