Molecular biology

Introduction  to  molecular  biology  

Molecular  biology  Refers to  the  study of  molecules  of  the  substances involved in process  of  life  .


The  tem  of  Molecular  biology was  first used  by  willian Astbury in  1945.
Molecular biology  is  a  new  branch  of biology delveloped  after 1950s.There are about  millian  species of  living organisms .These organisms are constructed by  Cells ..Cells are  the  structural  and functional  units  of  life..A multicellular organisms is  assembled by  thousands of cells. Thus  cells are  the  bulding blocks of  animals and  plants.
The  substance of  the  cell is  made  up of  chemicals in  the  form  of inorganic and  organic components.If  A cell is  disaasembled, it results in  averioty  of  chemical  molecules  .Thus  the  chemical  molecules  are  te  bulding  blocke  of  cells  .Even i the  ancient  time  ,Aristole and paracelsus conculed that 'all plant  and  animals ,however  complicated,are constitued of  a few  elements which  are  reapeated  in  each  of  them  '
The  chemical  component  of  cell can be broadly  clasified  in to  two  catogaries namely  inorganic  component and  organic  components  .The  in  organic components  include ,water,salts,ions,and  trace  element. The organic  components  includeds Protein, Corbohydrates ,Lipid  and  Nuclic Acids.
Of theses  the  organic compounds derived  from  corbon atoms ,standout as the  the  molecules  of  life .
The corban  containing  molecules of life are of  two types ,namely, micromolecules  or monomres and macromolecules  or  polymers .

The  micromolecules are small organic  compund and they inculde ,mono saccharides,aminoacids,fatty acids,,glycerols,pyridines,and pyrimidines, Macromolecules  are large complex organic  components  cosisting of  repeating unitsof  micromolecules.


In living  organisms ,there  are  3 types  of  polymers  ,Namely  Nuclic acids,plysaccharidesand  proteins  (poly pepties) Actual  molecular biology,, Moloecular biology  is  the study of  macromolecules of life process

Molecular biology  deals  with  the  follwoing  aspects  if  life  .

1.Structural oraganization  of  DNA .
2.DNA as  the genetic material,
3.Replication  of DNA.
4.RNA and  its  types.
6. Regulation  of  gene Expression,
7. Structure of  Protein  and  enzymes  

Historical Events in molecular biology

  

Though  Molecular Biology ,As a branch  of Biology ,was started in the 1950s,The  discoveries of  the  molecules  of  the  life date  back much  earlier .
In 1965,Mendel proposed that characters are  controlled by factor,Jhonson coined the genes for factor in 1909.

Miescher in 1869 isolated DNA molecules  from pus cells ,spermotozova and  from  nucleus of  RBC of birds,kunhe in 1877 coined term enzyme.

In 1930 Takemine,Aldrich,and  able ioslated the  first hormone epinephrine.In 1926 Janson And  Donath isolated the  first vitamin.

Schlesinger(1934)  demonsrated that bacteriophages are composed of  DNA and  protein. Avery, Mac Lead and McCarty proposed  that DNA is genetic materiasl.
Watson and  Crik in  1953 proposed the  double helix structure for  DNA.In1961 Jacob and Monod put  farward the  operon  concept .In 1968 Nirenberg and khorana worked out  the  complte genetic  code  .

In 1970 Knippers,Korenberg and Gefter isolated  DNA polymers II .
In  1971 Khorana and  Agarwal artificially synthesized te  gene  foe  alamine tRNA.

In 1978 Daniel,Nathans,Smith and  the  Arber discovered chemical  knives(Restriction  Enzymes )

Berg,Sanger and  gilbert(1980) Received  Nobel  prize for  genetic Engineering  

No comments:

Powered by Blogger.