Conjugation in bacteria was discovered by
Or
The sexuality in bacteria was established by

Options

A. Lederberg and Tatum
B. Zinder and Lederberg
C. Watson and Crick
D. Hershey and chase.

Answer

### Step-by-Step Solution

1. **Understanding Conjugation in Bacteria**: Conjugation is a process of genetic recombination in bacteria where genetic material is transferred from one bacterium (donor) to another (recipient) through direct contact.

2. **Identifying Key Players**: In conjugation, the bacterium that contains a plasmid (a small circular DNA molecule) is referred to as F positive (F+), while the bacterium that lacks the plasmid is called F negative (F-).

3. **Mechanism of Conjugation**: The F positive bacterium replicates its plasmid and forms a structure known as the conjugation tube, which connects to the F negative bacterium. Through this tube, the plasmid is transferred, allowing the recipient bacterium to also become F positive.

4. **Historical Context**: The discovery of conjugation and the establishment of sexuality in bacteria were significant contributions to microbiology.

5. **Correct Answer**: The discovery of conjugation in bacteria was made by **Lederberg and Tatum**.

### Final Answer
Conjugation in bacteria was discovered by **Lederberg and Tatum**.

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