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78 1. A cheek B mouth C eye D ear 2. A opening B closing C right D left 3. A makes up B does C contains D forms 4. A divide B separate C close D cut 5. A low B upper C posterior D inferior 6. A smell B vision C hearing D taste 7. A tissue B cell C mass D membrane 8. A like B as C if D as if 9. A enzymes B bones C teeth D glands 10. A in B if C of D at 11. A salivary B mucous C large D lymphatic 17. Read the previous text more attentively, entitle it. Define the main idea of the text and each paragraph. Make up the list of expressions necessary for describing the organs and structures of the oral cavity. Reading 3 18. a) Read the following text with the help of a dictionary. Translate it. b) Remember the underlined words and word combinations. Digestion in the Mouth The digestive system begins above with the cavity of the mouth and ter‑ minates below at the anus, traversing in its course the length of the thoracic and abdominal cavities. After entrance into the mouth the food undergoes a twofold reduction (treatment  1 ): mechanical and chemical ones. The frst process is called mas‑ tication. The food is broken up by the teeth, ground into small particles, moistened and softened by saliva. Saliva is slightly alkaline in reaction with a pH between 6.35 and 6.85. It consists of 99.5% water and 0.5% total sali‑ va. The amount secreted in 24 hours is 1,300 cc. The end product of mastica‑ tion is the bolus – a rounded mass of food thoroughly moistened with saliva. Salivary digestion is important in preparing the food for the changes that follow. Saliva dissolves some of the solid substances so that they are brought in contact with the taste buds; thus they stimulate appetite and re‑ sult in series of reflexes which increase the flow of gastric juice and augment salivary secretion as well. Moistened bolus of food turns into a plastic mass which is ready to be swallowed. Note 1 treatment – обработка