Prokaryotic cell division: Just before cytokinesis, the two daughter genomes in bacteria are found attached side by side to which cellular structure?

Introduction / Context:
Unlike eukaryotes, prokaryotes lack a nucleus and mitotic spindle. Their chromosomes replicate and segregate using mechanisms coordinated with the cell membrane and cytoskeleton. Understanding where DNA is anchored helps explain bacterial chromosome segregation before division.

Given Data / Assumptions:

• Organism: prokaryote (bacterium).
• Stage: just before cell division.
• Two daughter genomes are positioned side by side.

Concept / Approach:
Bacterial replication initiates at the origin (oriC). Newly replicated origins are tethered to the cell membrane/inner surface at midcell or quarter positions via protein assemblies, coordinating with septum formation. Membrane growth and cytoskeletal elements (e.g., FtsZ ring) help segregate nucleoids as the cell elongates and constricts.

Step-by-Step Solution:

Verification / Alternative check:
Classical models and imaging show oriC–membrane interactions and the Z-ring guiding septum assembly at the membrane.

Why Other Options Are Wrong:

Common Pitfalls:
Transferring eukaryotic vocabulary (centromere, equatorial plate) to bacteria. Prokaryotes use membrane- and cytoskeleton-coordinated segregation instead.

Final Answer:
Cell membrane (plasma membrane at midcell).