CBSE Class 9 Answered
Expert Answer
Contribution of Scientists in the Study of Cells
|
SCIENTIST |
YEAR |
DISCOVERY |
|
Zacharias Jansen and Hans |
1590–1610
|
Discovered the first ‘compound microscope’ |
|
Robert Hooke |
1665 |
Discovered ‘cell’ |
|
Robert Brown |
1828 |
a. Reported ‘Brownian movement’ in cells b. Described ‘nucleus’ as a central feature of a plant cell |
|
M. J. Schleiden |
1838
|
Described ‘nucleoli’ and proposed the ‘Cell theory’ along with T. Schwann |
|
T. Schwann |
1839 |
Applied ‘Cell theory’ to animals |
|
J. E. Purkinje |
1840 |
Named cell contents as ‘protoplasm’ |
|
R. Virchow |
1855 |
Stated that all cells arise from pre-existing cells, i.e. ‘Omnis cellulae e cellula’ |
|
Schultze
|
1861
|
Identified the cell as a living substance and called the protoplasm the ‘physical basis of life’ |
|
M. Knoll and E. Ruska |
1932 |
Invented the ‘electron microscope’ |
|
J. D. Watson and F. H. C. Crick |
1953 |
Proposed the double helix model for ‘DNA’ and received the Nobel Prize in 1962 |
Application Videos
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Plant and Animal Cells
This video talks about the basic parts of cell.
Concept Videos
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Cell - The Fundamental Unit of Life
Discusses the discovery of Cell, Cell theory, Various shapes and sizes o...
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Cell - The Fundamental Unit of Life
Discusses the discovery of Cell,Cell theory,Various shapes and sizes of ...
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Cell - The Fundamental Unit of Life
Discusses the discovery of Cell,Cell theory,Various shapes and sizes of cel... -
The Fundamental Unit of Life
The Fundamental Unit of Life, Introduction to Cell
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