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Plant Growth and Mineral Nutrition — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYPlant Growth and Mineral Nutrition3 Marks
Question
Discuss about discovery of cytokinin.
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Answer

  1. Cytokinins are growth promoting hormones that stimulate cell division.
  2. Skoog and Miller discovered first cytokinin when they were investigating nutritional requirements of tobacco callus culture.
  3. It was observed that the callus proliferated when there was addition of coconut milk as supplement.
  4. The degraded sample of herring (fish) sperm DNA also showed similar growth of tobacco callus. They named the substance as kinetin.

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