DNA replication

DNA Replication :
-existing DNA strands to serve as templates for new complementary strands
- Semiconservative, new DNA has 1 old 1 new strand

1, Helicase untwist and separate template DNA strands from the origin of replication, break hydrogen bonds and moves along the direction of leading strand
2, SS binding proteins keep the unpaired template strands apart during replication
3, Gyrase releases any tension brought about by the unwinding of the DNA strands
4, Primase attaches RNA primer as soon as there is a single strand
5, DNA polymerase 3 catalyze the elongation of new DNA and attaches free flowing nucleosides on to the single strand
6, Leading strand is replicated continuously towards replication fork while lagging strand is replicated in okazaki fragments. The growing direction of the new DNA strand is always 5 to 3. Therefore leading strand   always starts with 3 prime.
7, DNA polymerase 1 checks over the new replicated DNA strand and remove the RNA primer.
8, DNA ligase adds sugar phosphate backbone between the Okazaki fragments ( fill in gaps)

list of Enzymes
DNA polymerase 3
DNA polymerase 1
DNA ligase
helicase
gyrase
primase

Replication fork is where the parental DNA strands hasn't untwist. Replication bubbles allow DNA replication to speed up therefore the untwisted DNA would not be attacked by enzymes while replicating.

5 famous geneticists

Kary Mullis (1944- present)
year of fame :1993
famous publication: invention of PCR( polymerase chain reaction)
Contributions: Polymerase Chain Reaction is used to amplify small pieces of DNA into thousands and millions copies of this certain piece of DNA. This technique is now used in the medical, biotechnology, forensic and genetic fields.

Rosalind Franklin(1920-1958)
year of fame: 1958 (after her death)
famous publication: Her work on the x-ray diffaction images of DNA. Her work was actually the data that brought Watson to his discovery of the Double Helix.
contributions: She was first to be able to see the X shape of the DNA ladder.

James D. Watson( 1928-)
year of fame: 1962
famous publication: Watson and Crick published their paper to the scientific journal Nature to reveal the true shape of DNA, the double helix.
contributions:
Watson along with Crick's help, discovered the form of DNA and the significance of the nucleic acids.

Frederick Sanger(1918 -)
year of fame: 1958
famous publication: Sanger method developed by Sanger was a technique to do DNA sequencing.
contributions: Sanger method is now widely used to determine the order of the nucleic acids. It is one of the most efficient and easiest method available for DNA sequencing.

Gregor Mendel (1822-1884)
time of fame: 20th century
famous publication: Experiments on Plant Hybrization was his work done to show dominant and recessive traits in inheritance.

contributions: He is known as the father of modern genetics. He is the first to begin the studies of the genetics field