Q1.
Investigation: What happens to food inside your mouth? — “What happens to food after we eat it?”, she wondered.
Answer
Inside the mouth, food is cut, torn, crushed and ground by the teeth, mixed by the tongue, wetted by saliva, and turned into a soft mush that can be swallowed easily. Digestion actually starts right there in the mouth.
Follow one bite of roti, step by step.
- The front teeth (incisors) bite off a piece.
- The tongue pushes that piece to the back teeth.
- The premolars and molars crush and grind it into small bits.
- Saliva — the watery juice made in the mouth — flows in and wets the food.
- Saliva also begins to break down the food. That is why a piece of roti or rice starts tasting slightly sweet if you keep chewing it.
- The tongue rolls the wet bits into a soft, slippery ball, or mush.
- Now it is smooth enough to be swallowed safely, and it slides down easily.
Bite → chew → saliva mixes in → mush → swallow
Why chewing matters so much: The stomach has no teeth. Whatever we swallow whole, the stomach has to deal with as it is. Chewing breaks the food into small pieces, so the stomach's work becomes easy and digestion is faster and better. That is Finding #10 in Disha's notebook.
Try it yourself: put a small piece of plain roti in your mouth and chew it slowly, thirty times, without swallowing. Notice two things — it turns into a soft paste, and it begins to taste a little sweet. The sweetness is the saliva at work.