Which process entails a bacterial cell taking up extracellular DNA and incorporating it into its chromosome?

Which process entails a bacterial cell taking up extracellular DNA and incorporating it into its chromosome?

• A. Transformation
• B. Transduction
• C. Conjugation
• D. Binary Fission

Answer: (A)

Uptake of naked DNA from the environment and its integration into the chromosome is the hallmark of transformation. In this process, competent bacterial cells take up extracellular DNA and, through homologous recombination, incorporate it into their own genome. This often relies on specific uptake machinery and proteins like RecA to mediate recombination, allowing new genetic traits to be stably inherited. Transformation explains how bacteria can acquire new abilities—such as antibiotic resistance—from DNA released by other cells, even without direct cell-to-cell contact. By contrast, transduction involves transfer of DNA via bacteriophages, conjugation requires a physical bridge between cells and transfer of DNA (often via a plasmid), and binary fission is simply cell division, not DNA transfer.

Uptake of naked DNA from the environment and its integration into the chromosome is the hallmark of transformation. In this process, competent bacterial cells take up extracellular DNA and, through homologous recombination, incorporate it into their own genome. This often relies on specific uptake machinery and proteins like RecA to mediate recombination, allowing new genetic traits to be stably inherited. Transformation explains how bacteria can acquire new abilities—such as antibiotic resistance—from DNA released by other cells, even without direct cell-to-cell contact.

By contrast, transduction involves transfer of DNA via bacteriophages, conjugation requires a physical bridge between cells and transfer of DNA (often via a plasmid), and binary fission is simply cell division, not DNA transfer.