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NTA Abhyas NEET2020BotanyBiological ClassificationPractice

Beijernick concluded that the cause of tobacco mosaic disease was not a filtrate toxin because

Options

  1. Athe infectious agent could not be cultivated on nutrient media
  2. Bthe infectious agent could be crystallized
  3. Cthe infectious agent reproduced and could be passed on from a plant infected with filtered sap
  4. Dthe sap was infectious even though it was filtered to remove bacterias.

Correct answer

D. the sap was infectious even though it was filtered to remove bacterias.

Step-by-step solution

M.W. Beijerinek demonstrated that the extract of the infected plants of tobacco could cause infection in healthy plants and called the fluid as contagium vivum fluidum (infectious living fluid). The virus was found to be smaller than bacteria because they passed through a bacteria proof filter.

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