Which mechanism uses bacteriophages to transfer DNA between bacteria?

• A. Transformation
• B. Transduction
• C. Conjugation
• D. Transcription

Answer: (B)

Transduction is the mechanism that uses bacteriophages to move DNA between bacteria. During a phage infection, the phage can accidentally package a piece of the host bacterium’s DNA into its capsid instead of the phage genome. When this phage goes on to infect another bacterium, the donor DNA can be introduced into the new cell and may recombine with its chromosome. This is different from transformation, where bacteria take up free DNA from the environment, and from conjugation, which requires direct contact between cells and a pilus to transfer DNA (usually via a plasmid). Transcription is just RNA synthesis from DNA and isn’t a method of DNA transfer.