The Fundamental Unit of Life Class 9 Extra Questions

CBSE Notes for The Fundamental Unit of Life Class 9 Extra Questions

A Cell is the structural and functional unit of all the living organisms, which is capable of carrying out all life processes. Robert Hooke observed honeycomb-like compartments, the microscope and named them ‘cells’. They were dead cells. In 1674, Leeuwenhoek discovered living cells in pond water. The cell theory was presented by two biologists – Schleiden (1838) and Schwann (1839). It was further expanded by Virchow (1855). There are two types of organisms based on the number of cells present in them: 

• Unicellular organisms: They are single-celled. For example Mycoplasma, Amoeba 

• Multicellular organisms. They possess two or more c cells for example plant and animal cells. Cells are enclosed by a plasma membrane. Please refer The Fundamental Unit of Life Class 9 Extra Questions for more information.