DNA REPLICATION

DNA replication, the basis for biological inheritance, is a fundamental process occurring in all living organisms to copy their DNA. This process is "semiconservative" in that each strand of the original double-stranded DNA molecule serves as template for the reproduction of the complementary strand. Hence, following DNA replication, two identical DNA molecules have been produced from a single double-stranded DNA molecule. Cellular proofreading and error-checking mechanisms ensure near perfect fidelity for DNA replication. In a cell, DNA replication begins at specific locations in the genome, called "origins". Unwinding of DNA at the origin, and synthesis of new strands, forms a replication fork. In addition to DNA polymerase, the enzyme that synthesizes the new DNA by adding nucleotides matched to the template strand, a number of other proteins are associated with the fork and assist in the initiation and continuation of DNA synthesis.

Download a PDF file (To save Right Click and "Save")
On "Roles of Nuclear Structure in DNA Replication" http://dnareplication.cshl.edu/content/free/chapters/04_laskey.pdf

For Notes on Bacterial Replication: (Right Click and "Save")
http://www.sjsu.edu/depts/Biology/facultystaff/soto/DNAreplication.pdf

Click below to see an animation on DNA replication and also make a point to see the quiz in it:
http://www.bioteach.ubc.ca/TeachingResources/MolecularBiology/DNAReplication.swf

Click for a You Tube Video:
http://in.youtube.com/watch?v=teV62zrm2P0

Notes on "An expanded view of bacterial DNA replication" (Right Click and "Save Taget As")
http://www.pnas.org/cgi/reprint/99/12/8342.pdf

Notes on "A Boradening View of Recombinational DNA Repair in Bacteria" (Right Click and "Save ")
http://www.genestocellsonline.org/cgi/reprint/3/2/65.pdf

Notes on "VIRAL DNA POLYMERASES" (Right Click and "Save ")
http://dnareplication.cshl.edu/content/free/chapters/16_coen.pdf

Details about "EUKARYOTIC DNA POLYMERASES" (Right Click and "Save")
http://labs.fhcrc.org/stoddard/MCB_542/hubscher_etal_2002.pdf

Details about "BACTERIAL DNA POLYMERASES" http://www.mun.ca/biochem/courses/3107/Topics/DNA_polymerases.html

Details about "DNA REPLICATION AND ENZYMOLOGY OF DNA REPLICATION" (Right Click and "Save ")
http://www.rocw.raifoundation.org/biotechnology/MScBioinformatics/geneticengineeringvirologyandvectordesign/lecture-notes/lecture-04.pdf

THE DNA

In 1951, the then 23-year old biologist James Watson traveled from the United States to work with Francis Crick, an English physicist at the University of Cambridge. Crick was already using the process of X-ray crystallography to study the structure of protein molecules. Together, Watson and Crick used X-ray crystallography data, produced by Rosalind Franklin and Maurice Wilkins at King's College in London, to decipher DNA's structure. This is what they already knew from the work of many scientists, about the DNA molecule:
DNA is made up of subunits which scientists called nucleotides.
Each nucleotide is made up of a sugar, a phosphate and a base.
There are 4 different bases in a DNA molecule:
adenine (a purine)
cytosine (a pyrimidine)
guanine (a purine)
thymine (a pyrimidine)
By rule the number of purine bases equals the number of pyrimidine bases, which is known as Chargaff's Rule.
The number of A equals to T & G equals to C
The basic structure of the DNA molecule is helical and supercoiled, with the bases being stacked on top of each other. DNA can adopt a more compact configuration due to supercoiling. The degree of supercoiling in the cell is carefully controlled by the action of topoisomerases.

Click below for THE ORIGNAL WATSON AND CRICK'S PAPER ON DNA published in NATURE.

http://www.scribd.com/share/upload/14657893/107tm56i1nquox4cx6hm

Click below for CRICK'S ORIGNALVIEWS ON DNA

http://www.scribd.com/share/upload/14657985/1thxqzrgb62k0tiun4jd

DNA structure: Revisiting the Watson–Crick double helix by Manju Bansal

http://www.scribd.com/share/upload/14658063/bz1wet545h64o5t82eb

To go into the cell and have a virtual tour of it showing the DNA molecule click below

http://www.pbs.org/wgbh/nova/genome/media/journeyintodna.swf

Click here to build your own DNA molecule:

http://learn.genetics.utah.edu/content/begin/dna/builddna/

And if you want to extract a DNA online visit this virtual Lab:

http://learn.genetics.utah.edu/content/labs/extraction/

To extract DNA from almost anything in your Lab:

http://learn.genetics.utah.edu/content/labs/extraction/howto/DNA_Extraction.pdf