ORAL CAVITY
10. Read the text and do the tasks.
1. The mouth, buccal cavity, or oral cavity is the first portion of the alimentary canal that receives food and begins digestion by mechanically breaking up the solid food particles into smaller pieces and mixing them with saliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth.
2. In addition to its primary role as the beginning of the digestive system, in humans the mouth also plays a significant role in communication. While primary aspects of the voice are produced in the throat, the tongue, lips, and jaw are also needed to produce the range of sounds included in human language. Another non-digestive function of the mouth is its role in secondary social and/or sexual activity, such as kissing.
3. The mouth is normally moist, and is lined with a mucous membrane. The lips mark the transition from mucous membrane to skin, which covers most of the body. The first space of the mouth is the mouth cavity, bounded laterally and in front by the alveolar arches (containing the teeth), and posteriorily by the isthmus of the fauces. The oral cavity is also known as the mouth which swallows food and drinks that then go down the esophagus and into the stomach.
4. The mouth plays an important role in speech (it is part of the vocal apparatus), facial expression, eating, drinking and breathing. Infants are born with a sucking reflex, by which they instinctively know to suck for nourishment using their lips and jaw. The oral mucosa is the mucous membrane epithelium of the mouth. It can be divided into three categories.
- Masticatory mucosa - keratinized stratified squamous epithelium, found on the dorsum of the tongue, hard palate and attached gingiva.
- Lining mucosa - non-keratinized stratified squamous epithelium, found almost everywhere else in the oral cavity.
- Specialized mucosa - specifically in the regions of the taste buds on the dorsum of the tongue.
5. The mucous membranes (or mucosae; singular mucosa) are linings of mostly endodermal origin, covered in epithelium, which are involved in absorption and secretion. They line various body cavities that are exposed to the external environment and internal organs. It is at several places continuous with skin: at the nostrils, the lips, the ears, the genital area, and the anus. The sticky, thick fluid secreted by the mucous membranes and gland is termed mucus. The term mucous membrane refers to where they are found in the body and not every mucous membrane secretes mucus. Body cavities featuring mucous membrane include most of the respiratory system.
10 A) True or false.
1. The mouth is the first portion of the digestive tract. __
2. The mouth in humans also plays an important role in communication. __
3. The lips mark the transition from the tongue to skin. __
4. The oral mucosa can be divided into masticatory, lining and specialized mucosa. __
5. The mucous membranes line various body cavities. __
10 B) In which part of the text is said about:
6. not every mucous membrane secretes mucus __
7. mouth is the beginning of the digestive system __
8. mouth plays an important role in communicating __
9. skin covers most of the body __
10. oral cavity begins digestion __
10 C) Make up phrases with the words: alimentary, food, human, mucous, body, respiratory, significant, sucking, digestive, hard.
_____ canal
_____ membranes
_____ cavities
_____ system
_____ reflex
_____ system
_____ role
_____ language
_____ particles
______ palate
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