DNA - THE CODE OF LIFE
WHO DISCOVERED DNA?
- Who discovered the structure of DNA?
Maurice Wilkins and Rosalind Franklin (King's College in London 1950's) were trying to work out the structure of DNA
they took an experimental approach, looking at x-ray crystallography (diffraction images of DNA)
Francis Crick and James Watson (Cavendish Institute at Cambridge) also became interested in the structure of DNA
they build a model out of brass plates and clamps and other laboratory equipment and realised that nucleic acids are
arranged like a twisted ladder:
two runners made of phosphates and sugars
a series of rungs made of pairs of organic compounds known as bases
- What about genetic replication?
Watson and Crick developed their ideas about genetic replication in a second article in Nature
the pairing of the bases (A=T and C=G) suggested that given a sequence of bases in one strand, the other was automatically
determined
this meant that when two strands separated, each served as a template for a complementary new chain (each strand
would replicate)
Francis Crick and Sydney Brenner provided genetic proof that a triplet code was used in reading genetic material in DNA
and transferring that information from the nucleus to the cytoplasm via RNA --> where proteins are made
- Who won the Nobel prize?
of the 4 DNA researchers, Rosalind Franklin had many degrees in Chemistry --> she worked alone and suspected than DNA
molecules were helical but was reluctant to announce her finding without sufficient evidence
, she dies of cancer at 37-years
in 1962, when Watson, Crick and Wilkins won the Nobel prize for physiology/medicine, Franklin had died
______________________________________________________________________________
DNA - THE CODE OF LIFE
nucleic acids have been called the 'molecules of life' as they have the capacity to store the information that controls cellular
activity and the development of the entire organism
they do this by controlling the synthesis of proteins
proteins make up the structure of the body
since enzymes are proteins, they also control the chemical process inside cells
the two nucleic cells found in cells:
Deoxyribonucleic acid (DNA)
Ribonucleic acid (RNA)
____________________________________________________________________________
WHERE IS DNA FOUND?
, DNA is found in the nucleus of a cell where is forms an important part of the chromosomes that make up the chromatin
network
^ chromatin -- chromosomal material made up of DNA, RNA and histone proteins as found in a non-dividing cell
the DNA molecule is coiled so that long structures can fit inside the nucleus
2 meters of DNA squeezed into each human cell
- Extracellular DNA?
small amounts of DNA are found outside the nucleus:
in mitochondria in plants and animals
in chloroplasts in plants
this is called extranuclear DNA
- How is DNA made up?
the shape is like a long, twisted ladder
WHO DISCOVERED DNA?
- Who discovered the structure of DNA?
Maurice Wilkins and Rosalind Franklin (King's College in London 1950's) were trying to work out the structure of DNA
they took an experimental approach, looking at x-ray crystallography (diffraction images of DNA)
Francis Crick and James Watson (Cavendish Institute at Cambridge) also became interested in the structure of DNA
they build a model out of brass plates and clamps and other laboratory equipment and realised that nucleic acids are
arranged like a twisted ladder:
two runners made of phosphates and sugars
a series of rungs made of pairs of organic compounds known as bases
- What about genetic replication?
Watson and Crick developed their ideas about genetic replication in a second article in Nature
the pairing of the bases (A=T and C=G) suggested that given a sequence of bases in one strand, the other was automatically
determined
this meant that when two strands separated, each served as a template for a complementary new chain (each strand
would replicate)
Francis Crick and Sydney Brenner provided genetic proof that a triplet code was used in reading genetic material in DNA
and transferring that information from the nucleus to the cytoplasm via RNA --> where proteins are made
- Who won the Nobel prize?
of the 4 DNA researchers, Rosalind Franklin had many degrees in Chemistry --> she worked alone and suspected than DNA
molecules were helical but was reluctant to announce her finding without sufficient evidence
, she dies of cancer at 37-years
in 1962, when Watson, Crick and Wilkins won the Nobel prize for physiology/medicine, Franklin had died
______________________________________________________________________________
DNA - THE CODE OF LIFE
nucleic acids have been called the 'molecules of life' as they have the capacity to store the information that controls cellular
activity and the development of the entire organism
they do this by controlling the synthesis of proteins
proteins make up the structure of the body
since enzymes are proteins, they also control the chemical process inside cells
the two nucleic cells found in cells:
Deoxyribonucleic acid (DNA)
Ribonucleic acid (RNA)
____________________________________________________________________________
WHERE IS DNA FOUND?
, DNA is found in the nucleus of a cell where is forms an important part of the chromosomes that make up the chromatin
network
^ chromatin -- chromosomal material made up of DNA, RNA and histone proteins as found in a non-dividing cell
the DNA molecule is coiled so that long structures can fit inside the nucleus
2 meters of DNA squeezed into each human cell
- Extracellular DNA?
small amounts of DNA are found outside the nucleus:
in mitochondria in plants and animals
in chloroplasts in plants
this is called extranuclear DNA
- How is DNA made up?
the shape is like a long, twisted ladder
