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Question:

Which of the following is correct?

All fungi are filamentous.

Virus have only DNA as genetic material.

None of the above.

Transfer of DNA from one bacteria to another bacteria cannot take place.

Solution:

a) Fungi have a filamentous form called hyphae. The hyphae are made up of long chains of cells joined end to end by cross walls called septa (septate) or without septa (aseptate). However, some fungi like Yeast do not form hyphae and are single-celled. So, all fungi are not filamentous. Hence, statement A is incorrect.
b) Transfer of genetic material from one bacterium to other can take place by the following methods:

  1. Transformation- It is the process in bacteria by which free DNA is incorporated into a recipient cell from the surrounding as naked DNA.
  2. Transduction- It is the process by which DNA is transferred from one cell to other by a bacterial virus.
  3. Conjugation- It is the process of transfer of the genetic material from one cell to another by means of a conjugation tube.
    So, DNA transfer can take place from one bacterium to other. Hence, statement B is incorrect.
    c) Viruses contain genetic material enclosed in a protein capsid. The genetic material could be either DNA or RNA but not the both. Hence, statement C is incorrect.
    So, the correct answer is 'None of the above'.