Question

The origin of replication in bacteria is called

• A. OriC
• B. Promoter
• C. Enhancer
• D. Terminator

Hint:

Remember the important DNA regions: \[ \boxed{\text{OriC} \rightarrow \text{Origin of DNA Replication}} \] \[ \boxed{\text{Promoter} \rightarrow \text{Start of Transcription}} \] \[ \boxed{\text{Terminator} \rightarrow \text{End of Transcription}} \] OriC is found in bacterial chromosomes and plasmids where DNA replication begins.

Answer 1

The Correct Option is A

Concept: DNA replication begins at a specific nucleotide sequence called the origin of replication. In bacteria, there is usually a single origin known as OriC. Replication proceeds bidirectionally from this point until the entire circular chromosome is copied.

Step 1: Understand OriC.
OriC is a specific DNA sequence recognized by initiator proteins such as DnaA. These proteins bind to OriC and unwind the DNA double helix to begin replication. \[ \boxed{\text{OriC} \longrightarrow \text{DNA Unwinding} \longrightarrow \text{Replication Begins}} \]

Step 2: Differentiate from other DNA regions.

• Promoter is the binding site for RNA polymerase during transcription.
• Enhancers regulate gene expression in eukaryotes.
• Terminators signal the end of transcription.
• OriC specifically initiates DNA replication in bacteria.

Step 3: Choose the correct option.
Since bacterial DNA replication starts at OriC, \[ \boxed{Option (A) is correct \]