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For callus formation, auxin and cytokinin are required in what ratio?

Correct answer: C. Low auxin, very high cytokinin

  • A. Balanced
  • B. Only cytokinin required
  • C. Low auxin, very high cytokinin
  • D. Only auxin

Explanation

The ratio of auxin to cytokinin plays an important role in the effect of cytokinin on plant growth. Cytokinin alone does not affect parenchyma cells. When cultured with auxin but no cytokinin, they grow large but do not divide. When cytokinin is added, the cells expand and differentiate. When cytokinin and auxin are present in equal levels, the parenchyma cells form an undifferentiated callus, so it can't be used. More cytokinin induces the growth of shoot buds, while more auxin induces root formation.

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