1 2 3 4 As the excited Biology student was The enzyme running to class, The enzyme Primase Nuclease cuts out helicase attaches eager to take makes/attaches any mistakes or to specific regions notes, he/she fell RNA nucleotide mismatches allowing of DNA called and skinned their primers which will DNA polymerase Origins of knee. In order to allow the addition III to put on the Replication and make new cells to of DNA nucleotides correct base and unwinds the DNA replace those lost to the exposed ligase seals the by breaking the to the concrete, DNA strands. repair hydrogen bonds DNA must be between DNA replicated in the base-pairs. of Interphase. 5 6 7 8 DNA We now have two DNA elongation can Single-stranded Polymerase I must identical DNA now begin; leading binding proteins remove the RNA strands. Each one DNA strands will hold the two DNA nucleotides and has one original elongate toward the strands straight replace them with DNA strand and one replication fork and and apart. DNA nucleotides. newly synthesized lagging DNA strands Hydrogen bonds are DNA strand (this is will elongate away made between the called from the replication bases. semiconservative fork. replication)! 9 10 11 12 The lagging strand With the S-phase forms in segments The enzyme DNA DNA polymerase of Interphase called Okazaki ligase bonds seals III adds a DNA complete, G2 of fragments. DNA all gaps nucleotide to the 3’ the Cell Cycle will Polymerase III will (phosphodiester end of the RNA commence continue to build bonds) primers following followed by the fragments until complementary base Mitosis; the it reaches another pairing excited Biology primer…it then falls **What does student will now off. nuclease do? The leading strand gain new skin is elongated cells!! continuously while….
1 As the excited Biology student was running to class, eager to take notes, he/she fell and skinned their knee. In order to make new cells to replace those lost to the concrete, DNA must be replicated in the of Interphase. 2 The enzyme Primase makes/attaches RNA nucleotide primers which will allow the addition of DNA nucleotides to the exposed DNA strands. 3 Nuclease cuts out any mistakes or mismatches allowing DNA polymerase III to put on the correct base and ligase seals the repair 4 The enzyme helicase attaches to specific regions of DNA called Origins of Replication and unwinds the DNA by breaking the hydrogen bonds between DNA base-pairs. 5 DNA Polymerase I must remove the RNA nucleotides and replace them with DNA nucleotides. Hydrogen bonds are made between the bases. 6 We now have two identical DNA strands. Each one has one original DNA strand and one newly synthesized DNA strand (this is called semiconservative replication)! 7 DNA elongation can now begin; leading DNA strands will elongate toward the replication fork and lagging DNA strands will elongate away from the replication fork. 8 Single-stranded binding proteins hold the two DNA strands straight and apart. 9 The lagging strand forms in segments called Okazaki fragments. DNA Polymerase III will continue to build the fragments until it reaches another primer…it then falls off. 10 The enzyme DNA ligase bonds seals all gaps (phosphodiester bonds) **What does nuclease do? 11 DNA polymerase III adds a DNA nucleotide to the 3’ end of the RNA primers following complementary base pairing The leading strand is elongated continuously while…. 12 With the S-phase of Interphase complete, G2 of the Cell Cycle will commence followed by Mitosis; the excited Biology student will now gain new skin cells!!
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