In bacterial genetics, what term is used for a cell that has gained the physiological state required to take up naked (extracellular) DNA from its environment?

Introduction / Context:
Transformation is the uptake of free DNA by bacteria. Only cells in a specific physiological state—called competence—can bind, import, and integrate extracellular DNA. Competence may occur naturally (e.g., Streptococcus pneumoniae, Bacillus subtilis) or be induced artificially in the lab (chemical competence or electroporation).

Given Data / Assumptions:

• The question refers to uptake of naked DNA.
• We focus on the recipient cell's state, not the DNA type.

Concept / Approach:
Competent cells express surface structures and DNA transport machinery that facilitate binding and translocation of DNA across the membrane(s). Once inside, DNA can recombine with the chromosome or persist as a plasmid (if replication origin is compatible).

Step-by-Step Solution:

Verification / Alternative check:
Laboratory protocols routinely create competent E. coli cells (e.g., CaCl2 or electroporation), validating the terminology.

Why Other Options Are Wrong:

• Complementary/Liable: Not used in this context.
• Infected: Refers to phage or pathogen entry, not DNA uptake per se.

Common Pitfalls:

• Confusing competence (state) with competency (general ability); in microbiology, “competent” is standard.
• Assuming transformation always integrates DNA; plasmids may remain extrachromosomal.

Final Answer:
Competent