How bacteriophages deliver their genomes During infection of a bacterial cell, a bacteriophage adsorbs to receptors and then injects its nucleic acid through which structures to reach the cytoplasm?

Introduction / Context:
Bacteriophage infection begins with adsorption to specific bacterial receptors, followed by delivery of the phage genome into the host cytoplasm, where replication can proceed.

Given Data / Assumptions:

• Bacteria possess a cell wall and plasma membrane.
• Phages attach to surface structures like LPS, porins, or teichoic acids.
• The bacterial cytoplasm is the site of phage genome replication or expression.

Concept / Approach:
Most tailed phages pierce or traverse the cell wall and membrane to inject DNA directly into the cytosol. They do not deliver DNA “into” the membrane as a final destination, nor do bacteria have an endoplasmic reticulum or a nucleus.

Step-by-Step Solution:
Adsorption: tail fibers bind host receptors.Penetration: tail sheath contraction or channel formation permits DNA passage.Delivery: DNA crosses the wall/membrane barrier and enters the cytosol.

Verification / Alternative check:
EM studies and genetic evidence show rapid entry of phage DNA into cytoplasm, with empty capsids (ghosts) remaining outside.

Why Other Options Are Wrong:
Option b implies DNA remains in the membrane; option c incorrectly merges b; option d references an organelle bacteria lack; option e references a nucleus, also absent in bacteria.

Common Pitfalls:
Projecting eukaryotic cell structures onto bacteria; thinking the membrane is the final DNA destination.

Final Answer:
Cell wall into cytosol.