In which plant F.Skoog et. al observed 'callus during their experiments

Options

A. Tobacco
B. Coconut
C. Orange
D. Banana

Answer

**Step-by-Step Solution:**

1. **Identify the Researchers**: The question refers to the experiments conducted by F. Skoog and his colleagues.

2. **Determine the Plant Used**: The researchers observed callus formation in the inter-nodal segments of a specific plant. The options provided are tobacco, coconut, orange, and banana.

3. **Understanding Callus Formation**: Callus is an undifferentiated mass of cells that can form when plant tissues are cultured in a nutrient medium. This process often requires the presence of certain hormones.

4. **Hormones Involved**: In the experiments, auxins (a type of plant hormone) were used in conjunction with another substance to promote callus formation. The additional substance mentioned is coconut milk, which contains cytokinins.

5. **Cytokinins and Callus Formation**: Cytokinins are hormones that promote cell division and are crucial for the growth of the callus. The specific cytokinin identified by Skoog and Miller was named kinetin.

6. **Conclusion**: Based on the information provided, the plant in which F. Skoog et al. observed callus during their experiments is **tobacco**.

**Final Answer**: Tobacco

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