Page 26 - Ebook Digestive System Grade XI

Mechanical digestion, for example, occurs in the mouth when the teeth crush
Food. In chemical digestion, chemical reactions break down large molecules of
food into smaller ones. 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 propel food
processing in swallowing, helps clean the mouth,
and allowing the sound. The tongue is an organ of
muscles covered by a pink, moist tissue called the
Mucosa. On the surface of the tongue, there are
delicate hair-like structures called Papillae.

Figure 9. Tongue structure and function
Papillae are what make the tongue feel a little rough to the touch. Above the
papillae are thousands of nerve-like taste cells connecting 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 most extended 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 ducts that produce saliva. These glands also secrete amylase,
an enzyme that breaks down carbohydrates into maltose. Serves to dissolve Food,
facilitates swallowing, and protects the lining of the mouth against heat, cold,
acids, and bases. The salivary glands have three 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 ducts that 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
comprises layers of hard enamel, the dentin (bone
of the tooth) inside, and the pulp, which contains
blood vessels, nerve vessels, and other parts that
strengthen the teeth. In general, teeth play an
essential role in chewing Food and helping you
speak clearly. For that, its existence is necessary
for the human body. Several types of teeth are
arranged in the oral cavity with their respective
functions.

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