1. The living organisms vary in size from a few micrometers (e.g., microscopic bacteria) to more than 30
metres long (e.g., blue whale) and more than 100 meters tall (e.g., red wood trees of California).
2. The living organisms vary in longevity from a few days (e,g., mosquitoes) to several thousand years e.g. pine trees.
3. The living organisms range from colourless or transparent to brightly coloured birds and flowers.