- Books Name
- Science Made Easy Science Book
- Science Made Easy
- CBSE Class 9
• Cell is the structural and functional unit of life. It is the basic unit of life.
• It is discovered by Robert Hook in 1831 in cork slice with the help of primitive microscope.
• Leeuwenhoek (1674), discovered the free living cells in pond water with the improved microscope
• Robert Brown discovered the nucleus in the cell in 1831.
• Purkinje coined the term ‘protoplasm’ for the fluid substance of the cell in 1839.
The cell theory-
• The theory that all the plants and animals are composed of cells and the cell is the basic unit of life,
was presented by two biologists, Schleiden and Schwann.
• The cell theory was further expanded by Virchow by suggesting that all cells arise from preexisting