BSC 315 Lecture Notes - Lecture 7: Prokaryote, Deoxyribose, Nitrogenous Base

• School: University of Alabama
• Department: Biological Sciences
• Course: BSC 315
• Professor: Dr.Jeffrey Lozier

Document Summary

The watson and crick double helix model of dna a. Under appropriate experimental conditions, purified molecules of dna can align alongside each other in fibers to produce an ordered structure. Nucleotides are the building blocks of dna i. ii. iii. Remember: a nucleotide is composed of a deoxyribose sugar (dna), a phosphate group, and a nucleobase. Phosphodiester bonds link the 5" end of one nucleotide to the 3" end of another. Recall: purines (adenine and guanine - double rings) Nucleobases are attached covalently to the deoxyribose sugar (if only the nucleobase were attached, it would be a nucleoside) iv. That is all phosphodiester bonds must be connected from 3" to 5" a) b) And creates two distinct ends to the chains. 3" end - free 3" carbon atom v. The only difference between dna subunits is the specific nitrogenous base on each nucleotide.