The human digestive system involves several body parts. First, the process involves a breaking down of the food into smaller pieces inside the mouth; this is called mastication. This is accomplished by the grinding of the teeth and mixing of theanbsp;...
|Title||:||Classroom bulletin board activities kit|
|Author||:||Sonia Forseth Helton, Sonia M. Helton|
|Publisher||:||Prentice Hall Direct - 1987|