Dna project

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  • 1. DNA ReplicationBy John Matthews

2. P PSA TSPPA =AdenineThis is a DNA SG S Cmolecule before itstarts its journey in PPT=Thyminereplication. TheST A Sphosphates arePPabove the sugars. C=CytosineThe sugars have SG C Sbase pairs attachedPPto them. Adeninewith Thymine, and G=GuanineSA T SGuanine withCytosine. PPS=Sugar(Ribose)Hydrogen bondsSC G Sare in between thebase pairs whichPPP=Phosphatehold them together. ST AS P PSG C SPPSA T S 3. Step 1. DNA Helicase is basically the starting point inDNA replication, it is an enzyme that splits apart. TheDNA Replication takes place during the S Stage rightafter the G1 Stage and before the G2 Stage.DNA Replication 4. PPS A T SPP H =DNADNAS C G SHelicaseHelicasePPstarts theS T A Sprocess byPPsplitting the S G C Sbonds which PPcreate theS A T SReplicationPPForkS C G SPPS T AS PPS G C SP PS A T SP PS SC H GS PP ST APPSSGC 5. Step 2. RNA Primase begins its binding. RNA Primasecan attract nucleotides which bind to DNA nucleotidesdue to the hydrogen bonds between the basesDNA Replication 6. PPS A T SPPS C G SPPS T A S=RNA PrimsePPS G C SPPS A T SPPS C G SPPS T AS PPS G C SP PS A T SP PS SC GS PP STAPPSSGC 7. Step 3. The 53 Leading strand begins its journey byreading the template and continuously addingnucleotides. The 35 lagging strand adds more RNAprimase creating gaps or fragments known as Okazakifragments.DNA Replication 8. PPS A T SPPS C G SPPS T A SPPS G C SPPS A T SPPS C G SPPS T AS PPS G C SP PS A T SP PS SC GS PP ST APPSSGC 9. Step 4. In the Lagging strand the DNA Polymerase Iremoves the fragments. The gaps are closed with theaction of DNA Polymerase, and DNA Ligase.-DNA Replication 10. 5335RNA Primer RNA Primer 53 11. Step 5. The last step of DNA Replication is Termination.The DNA Polymerase reaches the ends of the strands. Itis not possible for the DNA Polymerase to fill the gapswhere the RNA Primers were. So the end of the parentalstrand where the last primer bind isnt replicated. Theseends consist of Telomeres. As a result a part of theTelomere is removed in every cycle of DNA Replication.DNA Replication 12. Step 6. DNA Replication is not complete until amechanism of repairs fixes all possible errors causedduring the replication. Enzymes like nucleases removethe wrong nucleotides and the DNA Polymerase fills thegaps.DNA Replication 13. 5 33 55 33 5 14. Telomeres are long stretches at the ends of thechromosome which are noncoding.Telomeres 15. Okazaki Fragments are when the replication fork openssufficiently, DNA Polymerase can begin to synthesize asection of complementary strand.Okazaki Fragments 16. A DNA Ligase has the job of stitching the OkazakiFragments together.DNA Ligase 17. Telomerase is an enzyme that adds telomere repeatsequences to the 3 end of DNA strands. By lengtheningthis strand, DNA Polymerase is able to complete thesynthesis of the incomplete ends of the opposite strand.Telomerase 18. Cancer is different from the regular tissue due to itsability to grow indefinitely. Most 85-90% cancers expresstelomerase atleast in the population of cancer stem cellsthat divide uncontrollably causing the Tumor to grow.Cancer 19. Transplanted Cells are removing cells from thepatient, and transforming them with the gene for theproduct that the patient has been unable to synthesize andreturn them to the patient.Transplanted Cells 20. Cloning is the replication of a single DNA moleculestarting from a single living cell to generate a largepopulation of cells containing identical DNA molecules.Cloning 21. Aging is a syndrome of changes that are deleterious, progressive, universal and thus far irreversible. Agingdamage occurs to molecules, cells, and organs.Aging 22. The purpose of DNA replication is to make an exact copyof DNA for other strands to be made. If DNA replicationwent wrong mutations could occur which could be fatalthe that strand of DNA or to the human body all together.The Purpose