Which of the following statements about conjugation is true?

• A. Transferring DNA between cells in conjugation requires a virus carrier.
• B. The donor and recipient cell must be in direct contact (touching) to transfer DNA.
• C. Conjugation can only occur between bacteria of the same species.
• D. Conjugation can occur with or without a conjugative plasmid.

Answer: (B)

Verified step by step guidance

1. Understand that conjugation is a process of horizontal gene transfer in bacteria, where genetic material is transferred from a donor to a recipient cell.
2. Recognize that for conjugation to occur, the donor and recipient cells must be in direct contact. This is typically facilitated by a structure called a pilus, which connects the two cells.
3. Identify that conjugation does not require a virus carrier. This distinguishes it from transduction, another form of horizontal gene transfer that involves viruses.
4. Note that conjugation can occur between different species of bacteria, not just within the same species. This allows for genetic diversity and the spread of antibiotic resistance genes.
5. Understand that conjugation typically involves a conjugative plasmid, which carries the genes necessary for the transfer process. However, in some cases, chromosomal DNA can also be transferred if integrated into the plasmid.