Chapter 6 Flashcards
Watson and Crick’s Model of DNA
1953
Double-stranded DNA structure
Rosalind Franklin
1st person to do x-ray diffraction of DNA
Led Watson and Crick to DS DNA structure
Did not receive proper credit (no Nobel Prize)
Instead, her supervisor, Maurice Wilkins, received the Nobel Prize
Key features in DNA
Double-stranded
Anti-parallel
Deoxyribose sugar
AT/CG base pairs
Sugar-phosphate backbone
Reads 5’ -> 3’
3 R’s of DNA
Replication
Repair
Recombination
DNA Replication
The process by which a copy of a DNA molecule is made
DNA Repair
The enzymatic processes that correct changes affecting the continuity or sequence of a DNA molecule
DNA Recombination
The process in which an exchange of genetic information occurs between two chromosomes or DNA molecules
3 key proteins involved with DNA replication
DNA Polymerase
DNA Primase
DNA Helicase
DNA Polymerase
Makes DNA by catalyzing the addition of subunits (nucleotides) to a polymer (DNA strand)
Is self-correcting
DNA Primase
Catalyzes the synthesis of RNA primers, which are required to initiate new DNA fragments on the lagging strand
DNA Helicase
Uses the energy of ATP hydrolysis to separate the strands of the parental DNA double helix
What enables DNA replication?
Base-paring
Where does DNA synthesis begin?
Replication origins
The replication fork is ___________
asymmetrical
Short lengths of _____ act as primers for DNA synthesis
RNA
_________ replicates the ends of eukaryotic chromosomes
Telomerase
What is the role of SS DNA-binding proteins in DNA replication?
To maintain the separated strands as SS DNA to provide access for the primase and polymerase
Sliding clamp
A circular protein clamp that allows the polymerase to slide during DNA replication
