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 known?

Open in App

Solution

(a) (i) Organism A is bacteria and (ii) substance B is acid.

(b) (i) Part C is the tooth enamel and (ii) part D is the dentine of the tooth.

(c) The small holes, E, are known as cavities.

(d) F is the pulp of the tooth.

(e) When bacteria (organism A) reaches the pulp (part F) of the tooth, it irritates the nerve endings and causes toothache.

Suggest Corrections

Similar questions

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 (rum 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?

Q. The top part A of the flask-shaped reproductive organ X in the flower of a plant secrets a surgery substance into its lower part B which goes towards the bottom part C of the flask-shaped organ. When a tiny grain D coming from the top part E of another reproductive organ Y i the flower falls on part A, it grows a long tube F through the organ X i response to the sugary substance and reaches the bottom part C of flask-shaped organ to carry out fertilisation.
(a) Name parts (i) organ X, and (ii) organ Y, inside the flower?
(b) Name parts (i) A (ii) B, and (iii) C, of flask-shaped organ.
(c) Name (i) grain D, and (ii) part E of organ Y.
(d) Name the tube F.
(e) What is the phenomenon of growing a long tube in response to sugary substance in the process of fertilisation in a flower known as?

The top part A of the flask-shaped reproductive organ X in the flower of a plant secretes a surgery substance into its lower part B which goes towards the bottom part C of the flask-shaped organ. When a tiny grain D coming from the top part E of another reproductive organ Y in the flower falls on part A, it grows a long tube F through the organ X in response to the sugary substance and reaches the bottom part C of the flask-shaped organ to carry out fertilisation.

(a) What is (i) organ X, and (ii) organ Y, inside the flower?

(b) Name parts (i) A (ii) B, and (iii) C, of a flask-shaped organ.

(d) Name the tube F.

(e) What is the phenomenon of growing a long tube in response to a sugary substance in the process of fertilisation in a flower knows as?

Which part of the tooth has soft material with nerves and blood vessels?

Q. Which part of the tooth, made up of a crystalline form of calcium phosphate, is the hardest substance in the body?

Join BYJU'S Learning Program