When a person eats sugary food, then organisms A present in his mouth act on sugar to produce a substance B. The substance B first dissolves the calcium salts from the top part C of the tooth and then from its middle part D forming holes E. These holes ultimately reach the part F in the lower part of tooth which contains nerves and blood vessels. The substance B irritates the nerve endings inside the tooth causing toothache.(a) What are (i) organisms A, and (ii) substance B?(b) What are (i) part C, and (ii) part D, of tooth known as?(c) By what name are the holes E in the tooth known?(d) Name the part F of the tooth.(e) What will happen if organisms A reach part F of the tooth?
(a) (i) Organism A is Bacteria.
(ii) The substance B is Acid
(b) (i)Part B of the tooth is known as Enamel.
(ii) part D of the tooth known as dentine.
(c) The holes on the tooth are known as Dental caries
(d) Part F is the Pulp cavity.
(e) On reaching Part F of the tooth, severe infection and inflammation will occur which will lead to severe pain.
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