DNA Replication in Bacteria—Termination Site Name On the circular bacterial chromosome (for example, Escherichia coli), what is the specific site designation for the replication termination region?

Introduction / Context:
Chromosomal DNA replication in many bacteria initiates at a defined origin (oriC) and terminates within a region containing replication terminator sites. In E. coli, these are termed "ter" sites and function with the Tus protein to halt replication forks in a directional manner.

Given Data / Assumptions:

• Replication proceeds bidirectionally from oriC.
• Termination requires fork traps to ensure orderly completion.
• ter sites interact with Tus to create polar fork barriers.

Concept / Approach:
Differentiate replication elements (oriC and ter) from unrelated genetic features. Stop codons terminate translation, not DNA replication. Stem–loop structures can function in transcription termination but are not the designated chromosomal replication terminators. The "pau" label is not a standard replication term in bacteria.

Step-by-Step Solution:

Verification / Alternative check:
Genetic maps of E. coli show multiple ter sites (e.g., terA, terB) arranged to create a replication fork trap opposite oriC.

Why Other Options Are Wrong:

• Stop codon: terminates translation, not DNA replication.
• Stem–loop: relevant to transcription termination; not specific to DNA replication termination.
• pau: not a recognized bacterial replication terminus designation.
• oriC: origin, not terminus.

Common Pitfalls:
Mixing up replication and transcription terminology; confusing origin (oriC) with terminus (ter).

Final Answer:
ter