Replication Flashcards
Rosalind Franklin
DNA double helix
helicase
breaks the two stands apart (creates replication fork)
ligase
glues the okazaki fragments together
replication fork
where it opens up
replication bubble
the whole bubble where transcription occurs
When DNA replication errors occur
1) Nuclease: cut out wrong portion
2) DNA Polymerase: replace with correct nucleotide
3) DNA ligase: stitch it all together
Telomeres
“Extra” DNA on the ends of chromosomes –> throwaway DNA to keep you from losing valuable info
Nucleic Acid Hybridization
base pairing of one strand of a nucleic acid to a complementary sequence ion another stand
what is DNA made of
deoxyribose, phosphate, and nitrogenous bases
semi-conservenant modle
new molecule is one parent strand, one compliment strand (correct model!)
conservennat modle
parent strands rejoin after copying (not true!)
dispersive modle
each new strand contains a section of both a parent and a copy
DNA polymerase 3
adds new nucleotides
primase
generates primers, starting place for DNA polymerase to begin making mRNA
topoisomerase
prevents the DNA double helix getting too tightly wound
what direction are new strands ALWAYS made in?
5 prime to 3 prime (new nucleotides can only be added to the 3 prime end)
Leading strand
synthesized continuously, towards replication fork, only one primer
Lagging strand
synthesized in a series of fragments called okazaki fragments, made away from replication fork
Plasmid
circular DNA found in bacteria
Restriction enzymes
cut DNA at specific sequences called restriction sites
Gel Electrophoresis
visualize restriction fragments based on size
Amplifying a DNA sequence
- DNA with target sequence
- heat resistance DNA polymerase
- Extra nucleotides
- Primers - start at the right spot
the reason for using Taq for PCR
it is heat stable and can withstand heating step of PCR
CRISPR
1) need a gene to look for and a protein that will search and cut it
2) get into the cell and attach to DNA sequence of interest and cut it
3) gene can be disabled by cutting out functional parts or a new gene provided to insert into curt
