IMPORTANT years in ncert :- 1731 - Many people of Bishnoi community sacrifice their lives saving trees (Jodhpur) 1770 - Priestley's experiment by Bell Jar, Mice & Mint plant, Candle. 1774 - Discovery of oxygen by Joseph Priestley 1838 - Matthias Schleiden-Cell Theory                                                    1829 - Theodore Schwann- Cell Theory 1850s -  Before industrialization => more white wing Moth 1854 - Julius von Sachs proved that glucose is formed in photosynthesis & stored as starch. 1855 - "Omnis cellula cellula" by Rudolf Virchow & complete the cell theory. 1856 - 1863 Mendel work on garden pea. 1860 - Hydroponics technique developed by Julie Von Sache 1865 - Mendel publishes his workon inheritance of character 1866 - Down's Syndrome discovered by Langdon Down. 1869 - DNA as a acidic substance was 1st identified by Friedrich Meischer & termed a "Nuclein" 1891 - Fossils of Java man discovered in Java           - Henking discovered X-body (X-chromosome) in insect. (XO- type sex determination) 1892 - Discovery of TMV by D.J. Ivanowsky 1898 -  M.W. Beijerinck demonstrated infectious nature of TMV           - Discovery of Golgi Body by Camillo Golgi. 1900 - Rediscovery of Mendel's work by ---> • Hugo de Vries            • Karl Corrence            • Tschemark 1902 - Chromosomal theory of inheritance given by Sutton & Bovery. 1905 - Law of limiting factors for plants given by Blackmann 1920 - After Industrialisation => more black moth 1928 - Frederick Griffith's Transformation  experiment on Streptococcus pneumonia bacteria 1933 – 1944 - Avery, Macleod McCarty used transformation principle of Griffith's experiment & concluded that DNA is genetic material. 1938 - Coelacanth/Lobe Fines caught in South Africa ---> Ancestor of amphibia. 1947 - At the time of our independence India's population, was approximately 350 million . 1950 -  Electron microscope invention             -  Tissue culture started 1951 - Family planning was initiated 1952 - Hershey & Chase experiment more correctly proved that DNA ie genetic material [ unquivocal_proof ] 1953  - Discovery of ribosome by George Palade.           - S.L Miller Experiment of evolution.           - Double helical structure model of DNA given by Watson & Crick. 1958 - Matthew Meselson of Franklin Stahl experiment (E. coli in NH4CI medium) proved that DNA replication is semiconservative )          -  Taylor study on vicia faba plant (used radioactive thymidind and proved  semiconservative nature of DNA) 1960 -  Green Revolution. 1963 - Restriction endonuclease isolated from E. coli. 1963 - Wheat varieties Sonalika f Kalyan Sona (High yield & Disease resistant ) introduced in INDIA 1966 - Derived semi dwarf varieties of rice introduced in India. 1969 - R.H. Whittaker proposed FIVE-KINGDOM Classification 1971 - Discovery of viroids by T.O. Diener           -  Govt. of India legalised MTP. 1972 - Fluid Mosaic model of plasma membrane by Singer & Nicolson           - 1st recombinant DNA developed by Stanley Cohen and Herbert Boyer           - National committee for environmental planning and Coordination was established.           - Wild life protection act in India. 1974 -  Water Act.  &  also Chipko movement 1980 -  Joint Forest movement 1981 - Air act.            - AIDS was fired reported            - Intrinsic growth rate of India (r= 0.0205)  1983 - Eli Lilly American company human Insulin from E. coli. 1984 - Bhopal Tragedy           - Ministry of Environment amd Forest. 1986 - Environment Act (NEPA) 1987 - Noise included in air pollution             - Montreal protocol (Canada) 1988 - National Forest Policy 1989 -  Montreal Protocol became effective. 1990 -  Delhi ranked 4th among 41 most polluted cities. 1990 - First clinical gene therapy was given to 14 yr old girl with ADA deficiency eye. - Human Genome Project (HGP) launched.