Nucleic Acids ppt2.2 Flashcards
(17 cards)
DNA Replication
-Before a cell divides, the DNA strands unwind and separate
-Each strand makes a new partner by adding the appropriate nucleotides
-The result is that there are now two double-stranded DNA molecules in the nucleus
-So that when the cell divides, each nucleus
contains identical DNA
STEP 1
Identification of the origin of replication (ori)
STEP 2.
The unwinding of the DNA
STEP 3:
FORMATION OF THE REPLICATION FORK
STEP 4:
ACTUAL DNA SYNTHESIS
STEP 5:
TERMINATION OF DNA REPLICATION
unwound DNA is stabilized by the _____ that prevent the reannealing of the DNA.
single-strand binding proteins (SSB)
further unwinding of the DNA is carried out by the enzyme
helicase.
supercoiling occurs ahead of the replication fork and is
taken care of by the enzyme
topoisomerase.
an enzyme called ______ forms a 10-nucleotide-long RNA primer over
primase
adds further nucleotides.
DNA polymerase III
the primer is removed by
DNA polymerase I,
help in the termination of the DNA replication process.
specialized termination sequences
Ter sequence is bound by
terminator utilization sequence.
act as anti-helicase and stop the further replication of DNA.
terminator utilization sequence.`
dna replication process
-DNA replication is the process by which a cell duplicates its DNA, ensuring that each daughter cell receives an identical genetic copy.
-It begins with the enzyme helicase unwinding the DNA double helix at origins of replication, creating two single strands.
-Primase synthesizes RNA primers, and DNA polymerase then adds nucleotides to build the new strands—one continuously (leading strand) and the other in short fragments (lagging strand).
- Finally, DNA ligase seals the gaps between fragments, completing the replication and ensuring accurate DNA transmission to the daughter cells.
seals the gaps between fragments
DNA LIGASE
