103. If the teeth are not cleaned regularly, they become covered with a sticky yellowish layer W of food particles and bacteria. Since layer W covers the teeth, the alkaline liquid X secreted by glands Y inside the mouth cannot reach the teeth surface to neutralize the acid formed by the action of organisms Z on sugary food, and hence tooth decay sets in. (a) What is W known as? (b) What is (i) X, and (ii) Y? (c) What are organisms Z? (d) State one way of removing layer W from the teeth.
If teeth are not cleaned well each day, plaque will lead to tooth decay or gum disease. If you do not remove plaque, it turns into a hard deposit called tartar that becomes trapped at the base of the tooth. Plaque and tartar irritate and inflame the gums.
