Page 21 - Ripples SCIENCE 7 - TEJPUR Edition 2024 Answer Key

3. In which part of the digestive system does most of the digestion of food and absorption

take place?

Ans. Small intestine.
4. Name the part of the digestive canal involved in the formation of faeces.

Ans. Large intestine
5. Name the hardest part of your teeth.

Ans. Enamel

6. Name the largest gland present in our body.
Ans. Liver

7. Name the part of alimentary canal where no digestion takes place.
Ans. Oesophagus is the part of alimentary canal where no digestion takes place.

F. Short-answer questions

1. What is buccal cavity?
Ans. Buccal cavity or oral cavity refers to the first part of the digestive system. It consists

of teeth, tongue and the salivary glands.

Teeth help in chewing the food and breaking down it into smaller pieces.
The salivary glands secrete saliva, which contain an enzyme called salivary amylase

that helps in breaking down of starch into simple sugar. Saliva also contains another

enzyme called lysozyme that helps in killing germs and bacteria that may have
entered in the mouth along with food. Saliva also helps in the lubrication of food

that makes its movement through alimentary canal smooth.
The tongue helps in the chewing of food by its movement in the mouth by mixing

saliva in it. Tongue also helps in swallowing the chewed food and tasting it.

2. Name the parts of the alimentary canal.
Ans. The parts of the alimentary canal are:

• Buccal cavity • Food pipe or oesophagus
• Stomach • Small Intestine

• Large Intestine • Anus.

3. Name the four types of human teeth.
Ans. The four types of human teeth are:

• Incisors  8 in number. Help in cutting and biting.

• Canines  4 in number. Help in holding and tearing the food.
• Premolars  8 in number. Help in crushing and grinding.

• Molars  12 in number. Help in fine grinding of food.

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