Binary fission Original Scenario-Based Download PDF

Questions

1. 1.

   A miniature research probe exploring a subterranean hydrothermal fissure monitors an ancient bacterium dividing under extreme thermal conditions. The probe's sensors detect a single circular DNA molecule initiating replication at a specific site while the cell steadily elongates and directs the duplicated genetic material toward opposite cell boundaries. A specialized protein scaffold then gathers at the midpoint to orchestrate inward wall synthesis and divide the cell into two genetically identical descendants. Based on the principles of prokaryotic binary fission, which statement accurately characterizes the biological mechanisms underlying this division process?

   • A) The cell condenses multiple linear chromosomes and disassembles its nuclear membrane so an extensive microtubule spindle apparatus can partition chromatids.
   • B) The cell replicates its single circular chromosome bidirectionally, segregates the origins toward opposite poles as it elongates, and divides via a septum formed by a contractile protein ring.
   • C) The cell undergoes unequal cytoplasmic budding where a small daughter outgrowth forms and receives a newly synthesized set of paired sister chromatids.
   • D) The cell aligns paired homologous chromosomes along a central metaphase plate to facilitate genetic crossing over prior to cytoplasmic cleavage.