Cell is the basic structural and functional unit of living organisms. Cell biology is branch of biology that deals with the study of cell in all respect of its structure and function.
The word cell came from Latin word ‘cellula’ meaning small room. Plant cell was the first cell to be discovered by scientists.
(i) Robert Hooke (1665) observed dead cell which resembled honeycomb like structures in cork (comes from bark of tree). He called these boxes 'cell'. He published what he observed under his self-designed microscope (primitive microscope) in his book ‘Micrographia’.
(ii) Antonie Van Leeuwenhoek (1674) was first to discover free living cell in pond water.
(iii) Robert Brown (1831) discovered the nucleus in cell.
(iv) Dujardin (1835) discovered fluid substance of cell and named Sarcode.
(v) J. E. Purkinje (1839) coined the term protoplasm for the fluid substances of the cell. It is living matter present inside the cell.
(vi) Huxley (1868) called protoplasm "The physical basis of life".
(vii) Rudolf Virchow (1858) – German pathologist established that all cells arise from pre-existing cells (“omnis cellula e cellula”).
A compound microscope is an optical instrument for forming magnified images of small objects consisting of an object lens and an eye piece, both lenses mounted in the same tube.
The discovery of electron microscope by Knoll and Ruska, in 1939 made it possible to observe and understand the complex structure of cell and its organelles.
(Session 2025 - 26)