Food (Classes VI-VIII) • Topic 1 of 4

Components of Food and Nutrients

Food is made up of nutrients, and CTET expects you to match each nutrient to its job and a typical source without hesitation. Carbohydrates are the energy-givers (rice, wheat, potato, sugar). Proteins are the body-building nutrients that grow and repair tissue (pulses, eggs, fish, milk, soyabean). Fats also give energy and, importantly, store it - gram for gram fats release more energy than carbohydrates, a fact CTET likes to test. Vitamins and minerals are protective nutrients, needed only in small amounts, that keep the body working and fight disease. Add roughage (dietary fibre, which has no nutrient value but keeps digestion moving and prevents constipation) and water (which carries nutrients and removes waste). The simple food tests belong here too: iodine solution turns starch blue-black, and a food smudged on paper leaving a translucent oily mark shows fat. On pedagogy: young children often think 'tasty' equals 'healthy', or that all food is one undifferentiated thing. The misconception that sugar or 'energy drinks' make you strong (rather than protein building the body) is common, as is the belief that fat is always bad. CTET tests this by asking how a teacher would help students classify their own tiffin foods into nutrient groups, or design a food-test activity - process over rote definition.

✅ Solved examples

1. A Class 6 child argues that since sugar gives instant energy, sweets are the best food for growing muscles. What is the correct teaching point, and what misconception is at work?
The misconception is confusing the energy-giving role of carbohydrates with the body-building role of proteins. Sugar (a carbohydrate) supplies energy but does not build muscle; muscles and tissues are built and repaired by proteins (dal, eggs, milk, fish). The teacher should let the child sort common foods into energy-givers vs body-builders so the distinction is discovered, not just told.
2. In a classroom food test, drops of iodine solution are placed on a slice of potato and the spot turns blue-black. What does this show?
It shows the presence of starch (a carbohydrate). Iodine turning blue-black is the standard test for starch, which is why potato, rice and bread give a positive result.
3. Which nutrient releases more energy per gram than carbohydrates and also serves as the body's energy store?
Fats. Per gram, fats give more energy than carbohydrates and act as the body's reserve store of energy (in oils, ghee, butter, nuts).
4. A pupil leaves a translucent oily mark when she rubs her paratha on paper but the mark vanishes for a piece of apple. What is being tested, and what does each result mean?
This is the test for fat. A permanent translucent (oily) mark on paper indicates fat is present (paratha, fried in oil). The apple leaves no lasting oily mark, indicating little or no fat.

✏️ Practice — try these, take hints as needed

1. Name the nutrient group that is mainly responsible for the growth and repair of body tissues.
Found in dal, eggs, fish, milk.
Called the body-building nutrient.
Proteins
2. Roughage gives the body no nutrient and yet doctors insist we eat it. Why?
It is dietary fibre.
Think about the movement of food through the gut.
Roughage (fibre) helps in digestion and prevents constipation by keeping the bowels moving; it adds bulk so waste passes easily.
3. Which simple laboratory test would a teacher use to show that bread contains starch?
A brown solution is added.
Watch for a blue-black colour.
The iodine test - iodine solution turns blue-black in the presence of starch.
4. A child believes drinking water is not really "eating" so it does not matter to the body. Correct the idea.
Water is still an essential component of food.
Think transport and waste removal.
Water is an essential component of food and diet: it carries nutrients to cells and helps remove waste from the body, so it matters greatly even though it gives no energy.

📝 Topic test — 8 questions

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