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DNA replication
Fichas del conjunto (6)
- 1Nucleic acids - DNA replicationSemi-conservative replication = partially keeps (conserves) part of the original strand
- 2—Semi conservative replication:
1) dna molecule begins to unwind
2) hydrogen bonds between bases break, exposing bases, it unzips
3) each strand of dna acts as a template for the formation of new complementary strand
- 34) free activated dna nucleotides in nucleus are attracted to their complementary exposed base (A-T and C-G) and link by hydrogen bonds 5) dna polymerase catalyses the condensation reactions between deoxyribose and phosphates of adjacent nucleotides to form a sugar phosphatebackbone6) two identical dna molecules formed, each containing an old parent strand and one new strand
This is semi-conservative replication - 4Other theories of dna replicationMeselsohn and Stahl - landmark experiment to support theory proposed by Watson and Crick
- 51) They chose bacteria as replicate every 20 minutes 2) 2 isotopes of nitrogen (N15 and N14) in growth medium (food for bacteria) so they could identify which were new nucleotides and which were in original DNA molecule. The N used to make the nitrogenous bases 3) N15 (labelled N) is a slightly heavier atom than N14 4) The bases and the way they pair not affected by different isotope
- 65) A density gradient can be produced by centrifuging Caesium Chloride (CsCl) at very high speed overnight 6) If DNA is also placed in tube it will remain intact and settle at point where it’s density equals that of the CsCl
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- AS - Level (Nucleic acids and their functions) Biology Fichas sobre DNA replication, creado por Emily Sutton el 25/02/2016.
- Creado por
- Emily Sutton
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