BIOL 1000 Chapter Notes - Chapter 12: Phosphodiester Bond, Complementary Dna, T & A (Professional Wrestling)
3 Mar 2017
School
Department
Course
Professor
Document Summary
Watson and crick discovered that a dna molecule consist of 2 polynucleotide chains twisted around each other into a right-handed double helix (held together by hydrogen bonds) Each nucleotide consists of deoxyribose (a carbon sugar); a phosphate group; a cyclic nitrogen containing a compound called a base. Adenine bonds with thymine through 2 hydrogen bonds. Guanine bonds with cytosine through 2 hydrogen bonds. The deoxyribose sugars are linked by phosphate groups to form an alternating sugar- phosphate backbone- connected by a phosphodiester bond. The two stands are complementary: makes dna suited to store & transmit genetic info. The sugar-phosphate backbones of the 2 complementary strands are antiparallel: (two strands of the dna double helix are antiparallel) Stacked (base-pairs) 34 apart, with 10 base pairs/turn (360 ) Chargaff"s rule- concentration of purines (t & c) = concertation of pyrimidines (a & g: t & a as well as g & c were present in dna with fixed interrelationship.
