Practical: A living organism as a whole system
A living organism is a whole system made of organs and organ systems that depend on one another. In a human the digestive system breaks down food, the circulatory system carries nutrients and oxygen to cells, the respiratory system takes in oxygen and gives out carbon dioxide, the excretory system removes waste, and the nervous system controls everything. If one fails, the others suffer too. In a plant the root system absorbs water and minerals, the stem conducts them, the leaf photosynthesises, and the flower and fruit take care of reproduction; the root and shoot systems depend on each other. When you run, for example, your muscles need a lot of energy: the heart beats faster, breathing quickens, sweat is released, and the brain coordinates it all. Making a model or a mind map helps us see and remember these links.
Practical work: draw a human silhouette on A3 card; mould the heart, lungs, stomach, intestine, brain and kidney from plasticine and glue them in place; write their names on coloured paper labels. In your group discuss: “which organs work together when you run?”. Another group makes a plant mind map on large paper and presents it. Safety: use blunt-tipped scissors with care; never put glue in the mouth.