Home Science: Nutrition, Meal Planning, Preservation and Everyday Safety
PSEB Matric Home Science asks you to use household science, not just recall it: choose a balanced diet for a named family member, name the nutrient missing in a deficiency disease, justify preserving mango pulp with sugar, act correctly in the first minutes of a burn, or identify an unknown fabric. Marks split between naming the concept and giving the reason, so write both.
Nutrients and deficiency diseases
Energy nutrients: carbohydrate and protein give 4 kcal/g, fat 9 kcal/g. Protein builds and repairs tissue; kwashiorkor is protein deficiency with oedema and a pot belly, while marasmus is protein-plus-energy deficiency with severe wasting. Learn the pairs: vitamin A – night blindness; vitamin D – rickets; thiamine (B1) – beri-beri; niacin – pellagra; vitamin C – scurvy; iron – anaemia; iodine – goitre. B-group and C vitamins leach into cooking water and are destroyed by overcooking and by baking soda; A, D, E and K are fat-soluble and are damaged when frying oil is reused.
Balanced diet and preservation
A balanced diet supplies energy, every nutrient, fibre and water in the right proportion - a full plate is not the same thing. Adjust for age, sex, activity, pregnancy, illness, budget and season. Preservation works by removing moisture (drying), binding water with sugar or salt by osmosis (jam, murabba, pickle), heat (pasteurisation at 63 °C for 30 minutes; sterilisation above 100 °C), cold (refrigeration slows microbes, it does not kill them) and acidity.
Worked example
A 15-year-old boy's lunch has 90 g wheat flour, 30 g dal and 100 g curd. Protein: wheat about 11 g per 100 g gives 9.9 g; dal about 22 g per 100 g gives 6.6 g; curd about 3 g per 100 g gives 3 g; total ≈ 19.5 g. If his daily need is 55 g and breakfast plus dinner supply 30 g, he is 5.5 g short - add 200 ml milk (≈6.4 g protein). Show the arithmetic; the method earns marks.
Marks-losing traps
Toothpaste or oil on a burn; cutting or sucking a snake bite; pouring fluids into an unconscious casualty; calling a costly diet balanced; swapping marasmus and kwashiorkor; forgetting that cotton burns with a paper smell and grey ash, while polyester melts into a hard bead.