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Class 5 The World Around Us — The mystery of food

Explain what makes food spoil, say how drying, oiling, canning and cooling each stop it, and name the teeth that cut, tear, crush and grind.

Name: ________________________

Before you start

One side of a jaw, from the front of the mouth to the back, with each group of teeth named.

1234
  1. 1. Incisors
  2. 2. Canines
  3. 3. Premolars
  4. 4. Molars

Look at the shapes rather than the names. Flat chisel edges at the front, a single point beside them, then broader tops with bumps towards the back — the shape of each tooth is the job it does.

  1. 1.Disha's mother mixes idli batter and leaves it out, and by morning it has risen and gone fluffy. What did that?

    • a) The warmth of the vessel it stood in
    • b) The water added while grinding it
    • c) Microbes from the air
    • d) The salt stirred into the batter

  2. 2.Sort each way of keeping food by which of the microbes' three needs it takes away.

    Groups: Takes the moisture away · Keeps the air out · Keeps the food cold

    • Drying tomato slices on a sunny windowsill
    • Pouring mustard oil over a jar of pickle
    • Keeping milk and butter in a fridge
    • Drying chillies on a mat in the sun
    • Sealing juice into air tight cans at a factory

  3. 3.Ghee is being made at home. Put the four steps in the order they happen.

    • Ghee is prepared
    • Water evaporates
    • Water separates from the butter
    • Heat butter

  4. 4.Match each group of teeth to the job it does on your food.

    • Incisors
    • Canines
    • Premolars
    • Molars
    • to grind
    • to cut
    • to tear
    • to crush

  5. 5.Why can we see mould on a spoiled uttapam when a single microbe is far too small to see?

    • a) Mould is not a microbe but a tiny plant
    • b) Mould gives off a colour that spreads over the food
    • c) Mould grows much larger than other microbes do
    • d) Mould is a colony of thousands of microbes together

  6. 6.Aditya has an upset stomach and is given curd. How does the curd help?

    • a) Its small microbes join the good microbes in the stomach and help digestion
    • b) It coats the stomach and keeps food from touching it
    • c) It has no microbes in it, so the stomach can rest
    • d) It is cold, so it slows the stomach down

  7. 7.Match each food to what it is preserved to make.

    • Roti
    • Mango
    • Lemon
    • Butter
    • Chillies
    • Fish
    • Lemon pickle
    • Ghee
    • Dried fish
    • Khakhra
    • Chilli powder
    • Aam papad

  8. 8.Which three things do microbes need in order to grow?

    • a) Moisture, sunlight and a container
    • b) Moisture, air and the right temperature
    • c) Sugar, oil and cold
    • d) Sunlight, soil and salt

Answer key — Class 5 The World Around Us — The mystery of food

  1. 1. c) Microbes from the air
  2. 2. Drying chillies on a mat in the sun → Takes the moisture away; Drying tomato slices on a sunny windowsill → Takes the moisture away; Pouring mustard oil over a jar of pickle → Keeps the air out; Sealing juice into air tight cans at a factory → Keeps the air out; Keeping milk and butter in a fridge → Keeps the food cold
  3. 3. 1. Heat butter 2. Water separates from the butter 3. Water evaporates 4. Ghee is prepared
  4. 4. Incisors → to cut; Canines → to tear; Premolars → to crush; Molars → to grind
  5. 5. d) Mould is a colony of thousands of microbes together
  6. 6. a) Its small microbes join the good microbes in the stomach and help digestion
  7. 7. Roti → Khakhra; Mango → Aam papad; Lemon → Lemon pickle; Butter → Ghee; Chillies → Chilli powder; Fish → Dried fish
  8. 8. b) Moisture, air and the right temperature