Tag: introduction to human digestive system

Questions Related to introduction to human digestive system

Wisdom tooth is the

  1. first molar tooth

  2. second molar tooth

  3. third molar tooth

  4. fourth molar tooth


Correct Option: C
Explanation:

A wisdom tooth or third molar is one of the three molars per quadrant of the human dentition. It is the most posterior of the three. Wisdom teeth generally erupt between the ages of 17 and 25

So, the correct answer is 'third molar tooth'

Teeth are the only part of the digestive system that physically breaks down food.

  1. True

  2. False


Correct Option: B
Explanation:

  • The digestive glands (salivary glands, pancreas, liver, and gallbladder) produce or store secretions that the body carries to the digestive tract in ducts and breaks down chemically. 
  • The teeth help in mechanical digestion by masticating (chewing) food.
  •  The whole process starts in the oral cavity, where the saliva from the salivary glands mixes with the food and starts to begin the breakdown of food. This semi-digested food then travels down to the small intestine, where secretions from the liver, gallbladder, and pancreas further act on the food particles. Hence, Teeth are not only part of the digestive system that physically breaks down food.
So, the correct answer is 'False'.

Upper molars in human dentition have

  1. Four roots

  2. Three roots

  3. Two roots

  4. Single root


Correct Option: B
Explanation:

Humans have four types of teeth, namely incisors, canines, premolars and molars. Each type of teeth has specific structure and function. The roots of teeth are embedded in the upper jaw and the lower jaw. Humans have 32 teeth, 8 incisors, 4 canines, 8 premolars and 12 molars. Canines and premolars have one root. Upper first premolars and lower molars have two roots. Upper molars have three roots.

Thus, the correct answer is 'Three roots.'

Incisor teeth in mammals are primarily for ________________.

  1. Weapons or for killing prey

  2. Grinding and chewing food

  3. Cutting and slicing food

  4. All of these


Correct Option: C
Explanation:

Incisors are the front four teeth which are used for cutting/biting and slicing the food, canines are the pointed teeth which helps in tearing the food whereas molars are the teeth which are used for Grinding and chewing of food particles. 

So, the correct option is 'Cutting and slicing food'

A diastema :

  1. Is a gap between two teeth

  2. Appears due to the absence of canine teeth in herbivores

  3. May occur in humans

  4. Is related to more than one option given above


Correct Option: D
Explanation:

A diastema is a gap between teeth mostly seen in the front teeth. It mainly occurs in mammals mostly in humans. It is caused by missing of teeth or undersized teeth.

So, the correct option is 'Is related to more than one option given above'

Permanent teeth start their appearance in children at the age of ......... years.

  1. 4

  2. 6

  3. 10

  4. 12


Correct Option: B
Explanation:

The arrival of second teeth occurs at 6 years +/- 6 months. With the exception of the wisdom teeth, the last of the secondary teeth come in around 12 years of age. 

Carnassial teeth are modified for

  1. Crushing

  2. Tearing

  3. Grinding

  4. Cutting


Correct Option: B
Explanation:

Carnassial teeth are the molar and premolar teeth modified for shearing flesh by having cusps with sharp cutting edges. They are typical of animals of the order carnivora (e.g., tigers, wolves), in which they are the first molars in the lower jaw and the last premolars in the upper.

Man bears $4$ kinds of teeth from front to the back of the jaw. Choose the correct order from the following.

  1. (i)- Incisor, (ii)- Canine, (iii)- Premolars, (iv)- Molars

  2. (i)- Molars, (ii)- Canine, (iii)- Premolars, (iv)- Incisor

  3. (i)- Molars, (ii-) Canine, (iii)- Incisor, (iv)- Premolars

  4. (i)- Incisor, (ii)- Premolars, (iii)- Molars, (iv)- Incisor


Correct Option: A
Explanation:

Incisors are the most anterior teeth. Canines - all mammals have a single canine in each quadrant. The premolars lie immediately posterior to the canines. In the upper jaw, they are found in the maxillary. The most posterior teeth in the jaws of most mammals are molars. Humans have two incisors, one canine, two premolars, and three molars, I2 C1 P2 M3, in each quadrant of their upper jaws. The numbers for each quadrant of the lower jaw are the same, and the general formula is written I2/2 C1/1 P2/2 M3/3. 

Match the following.

1. Incisors a. Grinding teeth
2. Canines b. Cracking teeth
3. Premolars c. Cutting teeth
4. Molars d. Tearing teeth
  1. 1 - b, 2 - d, 3 - a, 4 - c

  2. 1 - b, 2 - a, 3 - d, 4 - c

  3. 1 - c, 2 - b, 3 - d, 4 - a

  4. 1 - c, 2 - d , 3 - b , 4 - a


Correct Option: D
Explanation:
  • Incisors: The middlemost four teeth on the upper and lower jaws which help in cutting the food. So, they are referred to as cutting teeth.
  • Canines: The pointed teeth just outside the incisors which help in tearing of the food.
  • Premolars: Teeth between the canines and molars which helps in cracking of food.
  • The molars or molar: teeth are large, flat teeth at the back of the mouth. They are used primarily to grind food during chewing. 
So, the correct answer is  D.

A dental disease characterised by mottling of teeth is due to the presence of an ingredient in drinking water, namely

  1. Flourine

  2. Mercury

  3. Boron

  4. Chlorine


Correct Option: A
Explanation:

Dental fluorosis, also termed as mottled enamel is an extremely common disorder. It is caused by overexposure to fluoride during the first eight years of life. This is the time when most permanent teeth are being formed. Clinical dental fluorosis is characterized by staining and pitting of the teeth. In more severe cases all the enamel may be damaged.. The early symptoms of skeletal fluorosis, include stiffness and pain in the joints.  Hence, the dental disease characterised by mottling of teeth is due to the presence of an ingredient in drinking water is fluorine.

So the correct answer is ''fluorine''