Question

When a bacteriophage, in its lytic phase, carries some of the bacterium partially digested chromosome with it to another host cell, the process is called:

• A. Conjugation
• B. Generalized transduction
• C. Specialized transduction
• D. Transformation

Answer 1

The correct option is B

Generalized transduction

The correct option is B.

Explanation for correct option:

1. When certain proviruses turn into virulent viruses whereby causing lysis of the host cell, they may carry with their segments of the host’s DNA.
2. Such virus particles carrying a segment of the DNA from one host infect another host that is different from the first one, the latter may inherit some of the properties of the former host due to the transfer of DNA segment through the infecting phase.
3. This phenomenon of the transfer of genetic material from one bacterial strain to the other by the agency of the virus is called as transduction.
4. In conjugation, genetic material is generally transferred by a conjugation tube, when 2 strains come in contact. In the transformation, genetic material is released from one strain & a part may also be acquired from another strain, which thus gets transformed without coming into contact with the other strain.

Explanation for incorrect options:

Option A:

1. Conjugation is an exchange of the genetic materials within 2 cells that is in direct contact with each other or by forming a temporary bridge-like connection between 2 cells.
2. In conjugation, one cell act as a donor & another cell acts as a recipient. Bacterias exchange their genetic materials through this process.
3. It is termed as sexual reproduction of bacteria as 2 cells are involved and they mate with each other for their exchange.
   

Option C:

1. Specialized transduction is called the process by which a restricted set of bacterial genes is transferred to another bacterium.
2. The genes which get transferred (donor genes) depend on where the phage genome is located on the chromosome.

Option D:

1. Transferring the free DNA which is liberated from the donor (bacteria) to the extracellular surrounding results in assimilation and typically an expression of the hence acquired characteristic in the recipient bacteria.
2. This phenomenon is called bacterial transformation.

Final answer: When a bacteriophage, in its lytic phase, carries some of the bacterium's partially digested chromosome with it to another host cell, the process is called generalized transduction.