Chapter 15: DNA and Gene: Synthesis and Repair Flashcards
DNA structure
double-stranded, each strand consisting of deoxyribonucleotides
Deoxyribonucleotide
Deoxyribose sugar, phosphate group and nitrogenous base
How are phosphodiester linkages created
Formed when phosphate group of one nucleotide connects with the hydroxyl group the sugar of another nucleotide
2 major features of DNA
Backbone made up of sugar and phosphate groups of phosphodiester linkages
Series of bases that project from each sugar at the backbone
Double helix
Secondary structure of DNA, consisting of two anti-parallel DNA strands wound around each other.
Complementary base pairings
Association between specific nitrogenous bases of nucleic acids stabilized by hydrogen bonding
Semiconservative replication
If parental strands of DNA separated, each one could then be used as a template for synthesis of a new daughter strand.
Conservative replication
If the bases of both strands temporarily turned out from the helix, they could serve as a template for the synthesis of an entirely new double helix all at once.
Dispersive replication
Proposed that the parental double helix was fragmented into small pieces before replication and then each piece was replicated by either a conservative or semiconservative mechanism
DNA polymerase
Any enzyme that catalyzes the synthesis of DNA
Deoxyribonucleoside
Monomer used by DNA polymerase to polymerize DNA.
Structure: Consists of sugar deoxyribose, a base, and three phosphate groups
Origin of replication
Sequence of bases on a chromosome where DNA replication begins
Replication fork
Y shaped site where double stranded molecule of DNA is seperated into two single strands for replication on which DNA synthesis occurs.