Very Important Points of NCERT ❤️ || Biology ||

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 ๐Ÿ’ฅVery Important Points of NCERT ❤️:  


๐ŸŒŸ1. Genetic map discovered by Alfred Sturtevent. 

๐ŸŒŸ 2. Henking trace a specific nuclear structure (X-body) all through spermatogenesis in a few insects (1891). 

๐ŸŒŸ3. Down’s syndrome was first described by Langdon Down (1866) 

๐ŸŒŸ4. DNA (Nuclein) was first identified by Friedrich Meischer (1869). 

๐ŸŒŸ 5. X-ray diffraction data produced by Wilkins & Franklin. 

๐ŸŒŸ 6. Transforming principle was given by Griffith (1928). 

๐ŸŒŸ 7. Biochemical characterisation of transforming principle was given by 

Avery, MacLeod & Mc Carty. 

๐ŸŒŸ 8. Unequivoal proof that DNA is the genetic material came from the 

experiements of Hershey & Chase (1952). 

๐ŸŒŸ 9. Replication scheme was given by Watson & Crick. 

๐ŸŒŸ 10. Central dogma of biology was given by Crick. 

๐ŸŒŸ 11. The experimental proof that DNA replicates semiconservatively was 

given in prokaryotes by Meselson & Stahl (1958). 

๐ŸŒŸ 12. The experimental proof that DNA replicates semiconservatively was 

given in eukaryotes by Taylor (1958). 

๐ŸŒŸ 13. George Gamow (a physicist) proposed that codon was triplet. 

๐ŸŒŸ14. Har Gobind Khorana synthesizes RNA molecules with defined 

combination of bases (homopolyers & copolymers). 

๐ŸŒŸ 15. Nirenberg in cell-free system for protein synthesis finally helped the 

code to be deciphered. 

๐ŸŒŸ 16. Polynucleotide phosphorylase is called Severo Ochoa enzyme 

๐ŸŒŸ 17. Lac operon was given by Jacob & Monad. 

๐ŸŒŸ 18. Automated DNA sequencers worked on the principle of a method 

developed by Frederick Sanger 

๐ŸŒŸ 19. Frederick Sanger developed the method for determination of amino 

acid sequences in proteins. 

๐ŸŒŸ 20. DNA fingerprinting technique was developed by Alec Jeffreys. 

๐ŸŒŸ 21. Spontaneous generation theory was dismissed by Louis Pasteur. 

๐ŸŒŸ 22. Life comes from pre-existing life it is told by Louis Pasteur. 

๐ŸŒŸ 23. Oparin & Haldane proposed that the first form of life could have come from pre-existing non-living organic molecules.

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