Concept explainers
The terms conjugation, transduction, and transformation are used to describe three different natural forms of genetic transfer between bacterial cells. Briefly discuss the similarities and differences among these processes.
To review:
The similarities and differences among transformation, conjugation and transduction.
Introduction:
Genetic recombination is characterized by DNA (deoxyribonucleic acid) transfer in bacteria, from one organism, known as the donor, to another organism, known as the recipient. Such a genetic transfer is also known as horizontal gene transfer. In bacteria, obligate sexual reproduction is not present. Horizontal gene transfer is also known to occur between different species.
Explanation of Solution
The differences between transformation, conjugation and transduction are tabulated below.
Transduction | Transformation | Conjugation |
The transfer of the genes from one bacterium to another is referred to as transduction. | The incorporation of exogenous genetic material, resulting in the genetic alteration of a cell, is called transformation. | The genetic material transfer among the bacterial species with the help of sex pilus is called conjugation. |
It does not require for the occurrence of any physical contact between the recipient and the donor organism. | It requires the occurrence of physical contact between the recipient and the donor organism. | There is a direct cell-to-cell contact or a bridge-like connection between the two cells. |
Resistant to DNase. |
Not resistant to DNase. | Role of DNase is not defined. |
The similarities among transformation, conjugation and transduction are as follows:
1. All three, that is, transformation, transduction and conjugation, are examples of horizontal gene transfer as genetic information is not transferred from the parent to the offspring.
2. All three methodsincrease genetic variation as a part of genetic material is transferred from the donor to the recipient.
Therefore, it can be concluded that all three, that is, transformation, transduction and conjugation are methods of transferring genetic material, but they all differ in the process of transfer.
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Chapter 7 Solutions
Genetics: Analysis and Principles
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