An overview of living organisms
All living organisms feed, breathe, reproduce, grow and develop. They differ in cell type (prokaryotic or eukaryotic), cell size and way of feeding, and are placed in four worlds. The world of bacteria consists mostly of heterotrophic prokaryotes; they are tiny and visible only under a microscope. The world of fungi is made of eukaryotes that cannot move and feed heterotrophically; the body is built of thin threads called hyphae, and they reproduce by spores (from microscopic yeast to large mushrooms). The plant world (flora) is eukaryotes that cannot move; most carry out photosynthesis with chlorophyll and feed autotrophically: in light they make organic matter from carbon dioxide and water and release oxygen. The animal world (fauna) is freely moving heterotrophic eukaryotes; most many-celled animals have a nervous system and sense organs. Viruses are a cell-free form of life: they multiply only inside a living cell and show no signs of life outside it. Viruses cause diseases such as influenza and hepatitis. Handwashing, vaccination and seeing a doctor matter; antibiotics, which act against bacteria, do not work on viruses.
Set up four corners in the classroom: “Bacteria”, “Fungi”, “Plants”, “Animals”. The teacher says a picture or organism name (for example mushroom, juniper, snake, tuberculosis bacillus); pupils walk to the right corner and give the reason. Mark a separate “No cells” spot for viruses. Safety: walk slowly during the game.