Applying Science to Everyday Life, Agriculture and Technology
This domain tests how science is used in farming, food storage, water treatment, electricity and everyday tools.
Agriculture
Good practice starts with preparing soil and adding compost or manure, which improves structure and adds nutrients. Crop rotation helps because different crops take different nutrients and break pest cycles. Irrigation supplies water, but waterlogging can rot roots, so drainage matters. Pests and diseases are controlled by resistant varieties, careful timing, biological control or approved chemicals. Selective breeding chooses parents with useful features such as high yield or disease resistance.
Food, water and technology
Food is preserved by drying, salting or sugaring, canning and heating, refrigeration and fermentation. Salting and sugaring draw water out of microbes so they cannot grow; heating kills microbes; refrigeration slows their growth. Water treatment usually involves screening, sedimentation, filtration and chlorination. Electrical safety means insulated wires, dry hands, correct fuses and never mixing water with mains electricity. Everyday tools use simple machines - scissors are levers, a ramp is an inclined plane, a bottle cap is a wheel and axle.
Worked example
Why does salted meat keep longer than fresh meat? Salt draws water out of bacterial cells by osmosis, so the bacteria cannot grow and reproduce. The meat must be kept cool and covered as well, because salt does not kill every microbe.
Traps that cost marks
Compost is not the same as a concentrated fertiliser. More water is not always better - overwatering drowns roots. Two things happening together does not prove that one caused the other.