Question

Which of the following statements is correct for bacterial transduction?
A. Transfer of some genes from one bacteria to another bacteria through virus
B. Transfer of genes from one bacteria to another bacteria by conjugation
C. Bacteria obtain its DNA directly.
D. Bacteria obtain DNA from the surrounding.

Answer 1

Transduction is the mode of genetic material transfer in the bacteria. It is important for bacterial evolution. The bacteriophage plays an important role in carrying our bacterial transduction. There is no direct contact between the two bacteria.

Complete answer:
To answer this question, we must know about the mechanism of bacterial transduction.
Transduction is the process in which the genetic material is transferred from one bacterium to another using a vector called the bacteriophage(virus). This bacteriophage is capable of infecting bacteria and uses it as host to produce more viral copies.

The mechanism of transduction is:
Infection: The bacterial cell is infected by the bacteriophage.
The virus enters the host and uses lytic machinery to make multiple copies of phage DNA.
Assembly of the bacteriophage.

The transduction can take place by two methods-
a) Specialised transduction: In this the recombination between the chromosomes of the bacterium (host and the virus takes place which results in the formation of viral DNA containing bacterial DNA segment.
b) Generalised transduction: In this gene transfer takes place from the donor to the recipient cell. At times the DNA of the recipient fails to express.

Bacterial conjugation involves the transfer of genetic material between two bacterial cells through direct cell to cell contact forming a bridge like connection between two cells. After forming the bridge, the bacterial DNA moves from one bacterium to another. The bacterium takes up the DNA floating in the environment by the process of transformation. Thus, transduction is carried out using a host called the bacteriophage.

Thus the correct answer is option ‘A’.

Note: The transfer of genetic material in the bacterium takes place by three ways- transformation, transduction and conjugation. Only conjugation involves direct contact between the two bacterial cells. Transduction serves as an important process in gene transfer.