A. State True or False.
1. Canines help in tearing flesh.
2. Bacteria can cause cavities in the teeth.
3. Taking good care of our teeth can save them from decaying
4. Dentine is the hardest part of a tooth.
5. Permanent set of teeth has four types of teeth.
B. Match the Columns.
Column A
1. Incisors
2. Canine -
3. Premolar
4. Molar
Column B
(a) long and pointed
(b) outermost white I
YC) flat tooth (3)
Yd) chisel shaned to
Answers
Answer:
False. ...............
Explanation:
A.
1. ‘Canines help in 'tearing flesh.’
Canines is situated in the dental arches. They have a sharp and pointed surface. Canines help in tearing food. So, this statement is true.
2. ‘Bacteria can cause 'cavities' in the teeth.’
Bacteria live, move and reproduce. When we consume food and drinks, they feed on the sugars in it. They leave behind a waste on the surface of the teeth which is known as plaque. This causes acid formation and cavities. So, this statement is true.
3. ‘Taking good care of our teeth can save them from decay.’
By visiting a dentist regularly, brushing our teeth with toothpaste 'two times' a day, and reducing the intake of sugary food and drinks can save our teeth from decaying. This statement is true.
4. ‘Dentine is the hardest part of a tooth.’
Enamel is the hardest and outer part of the tooth. It is a mineralized tissue which can get damaged if not taken proper care.
Dentine is not the 'hardest part of the tooth' as it is a layer found under the enamel. This statement is false.
5. 'The permanent set of teeth has four types of teeth.'
Yes, this statement is true. There are 4 types of permanent teeth – 'Incisors', 'canines', 'premolars', and 'molars.'
B.
1. Incisors are a chisel-shaped tooth.
2. Canine is a long, pointed tooth.
3. The premolar is a cutting and grinding tooth.
4. The molar is a flat tooth.