Important Points of NCERT

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       ðŸŒŸ Important Points of NCERT 🌟

 1. 1770 : Joseph Priestley - Essential role of air in growth of green plant. 

2. 1774 : Joseph Priestley - Discovered O2.

3. 1831 : Robert Brown - Ist discovered and described nucleus. 

4. 1838 : Schleiden (German Botanist) - Work on plants. 

5. 1839 : Schwann(British Zoologist) - Work on both plants & animals. 

6. 1855 : Rudolf Virchow - Omnis cellula-e-cellula (cells arises from 

pre-existing cells). 

7. Life originate from pre-existing life : Pasteur (Yeast). 

8. Life originate from non-living (decaying & rotting matter) : Spontaneous generation. 

9. Life originate from pre-existing non-living organic molecules (RNA, Protein)- Oparin (Russia) & Haldane (England)- Chemical Evolution. 

10. 1856 - 1863 : Mendal experiment on garden pea. (7 years) 

11. 1860 : Julius von Sachs - Developed hydroponics. 

12. 1865 : Mendal published his work. 

13. 1866 : Langdon Down - Down’s syndrome. 

14. 1869 : Friedrich Meischer - Ist identified DNA and named it nuclein. 

15. 1891 : Henking - Discovered X-body. 

16. 1891 : Fossil discovered in Java - Homo erectus. 

17. 1892 : Ivanowsky - Discovered virus. 

18. 1898 : Beijerinek - Contagium vivum fluidum (infectious living fluid). 

19. 1898 : Camillo Golgi - Discovered (observed) G.B. 

20. 1900 : de Vries, Corre ns and von Tschermak inde pendently rediscovered Mendel’s results.

21. 1902 : Chromosome movement during meiosis has been worked out. 

22. 1905 : Law of limiting factor (Blackmann).

23. 1928 : Fredrick Griffith - Transforming experiment with Streptococcus pneumoniae (Diplococcus). 

24. 1935 : Stanley - Crystallised viruses. 

25. 1937 : Ramde o Misra obtained Ph.D. in Ecology from Lee ds university (U.K.). 

26. 1938 : Coelocanth fish caught in South Africa. 

27. 1945 : Fleming, Chain & Florey - Awarded Nobel prize. 

28. 1950 : Watson obtained Ph.D. on a study of the effect of hard X-rays on bacteriophage multiplication. 

29. 1951 : Family planning programme started in India. 

30. 1952 : Hershey & Chase-experiment on bacteriophage or Bacterial virus gives unequivocal proof that DNA is the genetic material. 

31. 1953 : Miller experiment - Methane, ammonia, hydrogen & water vapour. 

32. 1953 : Watson & Crick - Double helical structure of B-DNA & replication scheme. 

33. 1953 : Palade : Discovered ribosome. 

34. 1954 : Ramachandran - Triple helical model of collagen, published in Nature. 

35. 1954 : Crick complete d Ph.D. on a thesis “X-rays diffraction : polypeptides and proteins. 

36. 1958 : Meselson & Stahl - Work on E.coli proves semiconservative replication of DNA in prokaryotes. 

37. 1958 : Taylor - Work on Vicia faba proves semiconservative replication of DNA in eukaryotes. 

38. 1960 : Katherine Esau - Published “Anatomy of Seed Plants.” 

39. 1961 : Melvin Calvin - Nobel Prize. 

40. 1962 : Watson, Crick and Wilikins - Nobel Prize. 

41. 1963 : Wheat varieties (Sonalika & Kalyan sona) introduced. 

42. 1963 : Two enzyme responsible for restricting growth of bacteriophage in E.coli were isolated. 

43. 1966 : Derivative of IR-8 & Taichung native-I introduced. 

44. 1969 : Whittaker - Five kingdom classification.

45. 1971 : Govt. of India legalized MTP. 

46. 1971 : Diener- Discovered Viroid (free RNA without capsid). 

47. 1972 : Singer & Nicolson - Fluid mosaic model. 

48. 1972 : Stanley Cohen & Herbert Boyer - Formed Ist recombinant DNA. 

49. 1972 : Establishment of NCEPC - National Committee for Environmental Planning & Coordination. 

50. 1974 : Water act. 

51. 1980 : Joint forest management, (JFM). 

52. 1981 : AIDS was Ist reported. 

53. 1981 : Air act. 

54. 1983 : Eli Lily (An American company) produces insulin in E.coli by recombinant DNA technology. 

55. 1984 : Establishment of MOEF : Ministry of Environment & Forest. 

56. 1986 : Environment Protection Act. 

57. 1987 : Montreal protocol. Held in Montreal, Canada.


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