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Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because − (a) bacteria are resistant to the toxin (b) toxin is immature (c) toxin is inactive - Biology

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प्रश्न

Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because −

विकल्प

  • bacteria are resistant to the toxin

  • toxin is immature

  • toxin is inactive

  • bacteria encloses toxin in a special sac.

MCQ

उत्तर

Toxin is inactive

Explanation:

Bacillus thuringiensis produces protein crystals during a particular phase of its growth. These crystals have a deadly insecticidal protein. The Bt toxin protein exists as inactive protoxins; however, when an insect consumes the inactive toxin, it is transformed into an active form of toxin due to the alkaline pH of the insect stomach, which solubilises the crystals. The active toxin adheres to the surface of midgut epithelial cells, causing cell swelling and lysis, eventually leading to the insect's death, although it does not harm Bacillus.

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अध्याय 12: Biotechnology and its Applications - Exercises [पृष्ठ २१५]

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एनसीईआरटी Biology [English] Class 12
अध्याय 12 Biotechnology and its Applications
Exercises | Q 1 | पृष्ठ २१५

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