BIOL 112 Lecture 17: Lecture 17 - DNA Continued.pdf

• School: McGill University
• Department: Biology
• Course: BIOL 112
• Professor: Frieder Schoeck

Document Summary

Sequence of nucleotides is not constrained by the structure. Dna can accommodate any sequence, an arbitrary sequence can encode information ! The two strands of dna encode the same info in complementary form suggesting a method of replication (pull strands apart, both have same info encoded in a different way) ! 3 models of how reverse complimentary strands come about (dna. Semiconservative - each parent strand is a template strand. Conservative - original parent strands re-bound and daughter. Dispersive - bits of old and new are mixed together ! and remains with daughter strand (answer) ! strands are bound together ! replication): ! Experiment to determine which model is the correct one: semi-conservative ! Labeled dna with heavier n isotope (n15) then transferred into a medium with lighter n (n14); the replicated dna would have to be made with n14 ! 1st generation was half as light ! 2nd generation was half heavy, half light !