DNA Replication — Steps & Enzymes
This enzyme unwinds the DNA double helix at the replication fork.
helicase
The strand synthesized continuously toward the replication fork.
leading strand
The backbone of DNA consists of phosphate groups and this sugar.
deoxyribose
This scientist demonstrated bacterial transformation using rough and smooth strains of Streptococcus pneumoniae.
Frederick Griffith
Prokaryotic chromosomes are typically this shape.
circular
This enzyme synthesizes short RNA primers needed to start DNA replication.
primase
The strand synthesized discontinuously away from the fork.
lagging strand
These nitrogenous bases pair A–T and G–C.
complementary base pairs
This experiment proved that DNA, not protein, is the genetic material using bacteriophages.
the Hershey–Chase experiment
Eukaryotic chromosomes are organized as multiple linear DNA molecules inside this organelle.
the nucleus
The main enzyme responsible for adding nucleotides to the growing DNA strand in the 5′→3′ direction.
DNA polymerase III
Short DNA fragments produced on the lagging strand.
Okazaki fragments
The bond that links nucleotides along one DNA strand.
a phosphodiester bond
This scientist used X-ray diffraction to produce Photo 51, revealing DNA’s helical structure.
Rosalind Franklin
Prokaryotes usually have this number of origins of replication per chromosome.
one
This enzyme removes RNA primers and replaces them with DNA nucleotides in prokaryotes.
DNA polymerase I
The reason the lagging strand is synthesized discontinuously relates to DNA polymerase only working in this direction.
5′ to 3′
The major and minor grooves of DNA result from this helical structure.
the double helix
These two scientists proposed the double helix model of DNA in 1953.
James Watson and Francis Crick
Eukaryotic chromosomes contain many origins of replication to accomplish replication during this phase.
S phase
This enzyme seals nicks in the sugar-phosphate backbone by forming phosphodiester bonds.
DNA ligase
This structure forms where the double helix is opened and both strands are copied.
replication fork
Guanine pairs with this base using three hydrogen bonds.
cytosine
This conclusion from Griffith’s work described the transfer of genetic information between bacteria.
transformation
The ends of linear chromosomes that require special replication mechanisms in eukaryotes.
telomeres