Teeth

Q. The dental formula for human beings is .

1. 2.1.2.3
2. 2.2.1.3
3. 1.2.3.1
4. 1.2.3.4
5. 2.1.2.2

Q.

Define homodont and heterodont definitions.

Q.

Name the following types of teeth with their function.

1. A- Incisors- cutting and biting
   B- Canine- Chewing and grinding
   C- Premolar- Chewing and grinding
   D- Molar- Piercing and tearing
2. A- Incisors- Chewing and grinding
   B- Canine- Piercing and tearing
   C- Premolar- Cutting and biting
   D- Molar- Chewing and grinding
3. A- Incisors- Cutting and biting
   B- Canine- Piercing and tearing
   C- Premolar- Chewing and grinding
   D- Molar- Chewing and grinding
4. A- Incisors- Chewing and grinding
   B- Canine- Chewing and grinding
   C- Premolar- Piercing and tearing
   D- Molar- Cutting and biting

Q.

What is meant by milk teeth?

Q.

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 neutralise 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.

Q.

The primary dentition in human differs from permanent dentition in not having one of the following type of teeth?

1. Molars

2. Incisors

3. Premolars

4. Canine

Q.

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 milk teeth are also called temporary or ________ teeth.

Q. The correct dental formula for human beings is:

1. 2.1.2.3
2. 2.2.1.3
3. 1.2.3.1
4. 1.2.3.4

Q.

Glandular epithelium consists of columnar cells modified to secrete chemicals. It lines the glands, e.g. gastric glands, pancreatic lobules, intestinal glands etc.

1. True
2. False

Q.

Which type of teeth are used by carnivores for tearing flesh?

1. Canines

2. Premolars

3. Molars

4. Incisors

Q. Fill in the blanks :​
​
(viii) The human teeth appear in two sets, the first set is called which consist of only teeth. ​

Q. The dental formula for human beings is .

1. 2.1.2.3
2. 2.2.1.3
3. 1.2.3.1
4. 1.2.3.4
5. 2.1.2.2

Q.

Outer protective layer of skin, called epidermis is made up of ------ tissue.

Q.

Fat soluble Vitamins are:-

1. A, D and E

2. B, C and D

3. B, D and E

4. A, B and C

Q.

Write the dental formula of deciduous teeth and permanent teeth in humans.

Q.

Which type of teeth are used when a person is biting off an apple?

1. Canines

2. Premolars

3. Molars

4. Incisors

Q.

State the main function of the following.
Molar

Q. The hardest substance in human body is

1. Melanin
2. Dentine
3. Collagen
4. Enamel

Q. The number of incisors, molars, premolars and canines in the buccal cavity is

1. 8, 4, 8, 4
2. 8, 4, 8, 8
3. 4, 8, 8, 8
4. 8, 8, 8, 4

Q. ________ and ________ are used for chewing and grinding food.

1. Canines and premolars
2. Premolars and molars
3. Incisors and canines
4. Canines and molars

Q. The teeth present in humans are

1. Deciduous teeth
2. Permanent teeth
3. Milk teeth
4. All of the above

Q. Diastema is a toothless gap in the jaws of rabbit between ______________.

1. Incisors and premolars
2. Premolars and molars
3. Incisors and molars
4. Canines and molars

Q. Draw a neat labelled diagram of lateral section of a tooth.

Q.

The first set of teeth that lasts for about six years of age is called _____ .

1. milk teeth

2. permanent teeth

3. molar teeth

4. canines

Q. Hardest substance of the body is

1. Bone
2. Enamel
3. Cartilage
4. Tendon

Q. Number of teeth in man which grow twice are

1. 20
2. 4
3. 28
4. 8
5. 12

Q. Soham is 6 years old. He was playing in the garden. One of his teeth fell as he dashed a pillar. He started crying because he was hurt. He also felt that his teeth will never come back and he will not be able to eat chocolates. How will you console him?

1. By telling him that his tooth was milk tooth
2. By telling him that his tooth was permanent tooth
3. By telling him that his tooth will be replaced
4. Both A and C

Q.

Which among the two is the hardest substance of our body:enamel or dentine ?

Q.

(a) Describe the parts of our tooth with the help of a labelled diagram.
(b) What is meant by dental caries ? How are they caused ?
(c) What is dental plaque ? What harm can it do ? How can the formation of plaque be prevented ?