Page 26 - E-book Digestive System

Mechanical digestion, for example, occurs in the mouth, when food is crushed by
the teeth. In chemical digestion, chemical reactions occur which break down large
molecules of food into smaller molecules. Chemical digestion in the digestive
process is usually carried out and assisted by digestive enzymes, such as amylase
in the mouth.
a. Tongue
Functions as a taste bud, helping to propel
food in the process of swallowing, helps clean
the mouth and helps sound. The tongue is an
organ made up of muscles and covered by a
pink, moist tissue called the Mucosa. On the
surface of the tongue, there are fine hair-like
structures called Papillae.

Figure 9. Tongue structure and function
Papillae is what makes the tongue feel a little rough to the touch. Above the
papillae, there are thousands of nerve-like taste cells that connect the tongue
nerves to brain receptors. The average size of the male tongue is 8.5 cm, while the
female tongue is 7.9 cm. Noted, the longest human tongue size reaches 10.1 cm.
b. Salivary gland
The salivary glands or salivary glands in mammals are exocrine glands, which
are glands that have their own ducts, which produce saliva. These glands also
secrete amylase, an enzyme that breaks down carbohydrates into maltose. Serves
to dissolve food, facilitate swallowing, and protects the lining of the mouth
against heat, cold, acids, and bases. The salivary glands have 3 parts, namely:
1) Parotid gland, produces saliva in the form of water.
2) Submaxillary gland, produces sap that contains water and mucus.
3) Sublingual gland, produces sap that contains water and mucus
The salivary glands or salivary glands in mammals are exocrine glands, which are
glands that have their own ducts, which produce saliva. These glands also secrete
amylase, an enzyme that breaks down
carbohydrates into maltose.
c. Tooth
Teeth are body tissues that are very hard
compared to others. Its structure is made up of
layers of hard enamel, the dentin (bone of the
tooth) inside, the pulp which contains blood
vessels, nerve vessels, and other parts that
strengthen the teeth. In general, teeth play an
important role in chewing food, as well as
helping you to speak clearly. For that, its

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