Final answer:
DNA replication in bacterial chromosomes involves initiation, elongation, and termination stages. There are two replication forks formed at the origin of replication. The origins of replication are rich in AT nitrogenous bases due to their easier separation and initiation of DNA replication.
Step-by-step explanation:
The Three Stages of DNA Replication in Bacterial Chromosomes:
- Initiation: The replication begins at specific nucleotide sequences called origins of replication, which are rich in AT base pairs. The origin of replication is recognized by proteins that bind to the site. An enzyme called helicase unwinds the DNA and forms two replication forks at the origin of replication.
- Elongation: DNA polymerase adds nucleotides to the growing DNA strands. The leading strand is synthesized continuously in the 5' to 3' direction, while the lagging strand is synthesized discontinuously in Okazaki fragments.
- Termination: The replication process ends when the replication forks meet and successfully complete the replication of the entire bacterial chromosome.
In bacterial chromosomes, there are two replication forks formed at the origin of replication.
The origins of replication are rich in AT nitrogenous bases because AT base pairs have two hydrogen bonds compared to the three hydrogen bonds in GC base pairs. This makes the AT-rich sequences easier to separate and initiate DNA replication.