There was a time when biologists (the scientists who study living organisms) thought that whatever they could see with their naked eyes were the only living organisms. But with the invention of that marvellous 'magic tube', the microscope, hitherto invisible tiny life forms were seen for the first time. The scientists put any thing and almost everything under the microscope to see if they showed living characteristics. That was how Robert Hooke made the discovery of the cell. Thus began a new revolution in biology.

1. Life is a unique, complex organisation of molecules. (Explanation)
2. Discovery and early study of cells progressed with the invention and improvement of microscope. (Explanation)
3. Organisation is the manner in which smaller components of a system are arranged in a hierarchy to form bigger ones. (Explanation)
4. Living organisation differ from nonliving things in many aspects. (Explanation)