Scientist who first isolated cytokinin was

Options

A. White
B. Skoog
C. Letham
D. Miller.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Cytokinins**: Cytokinins are a class of plant hormones (phytohormones) that play a crucial role in promoting cell division (cytokinesis) and various growth processes in plants.

2. **Accidental Discovery**: The discovery of cytokinins, like many other phytohormones, was accidental. This means that the scientists did not set out specifically to discover cytokinins but stumbled upon them during their research.

3. **Research Context**: The first isolation of cytokinins was conducted by scientists who were studying the growth of tobacco plants. Specifically, they were working with the internodal segments of tobacco stems.

4. **Experiment Details**: The scientists, led by Skoog and his co-workers, grew these internodal segments in the laboratory. They observed that these segments could grow into a mass of undifferentiated cells known as callus.

5. **Substances Used**: During their experiments, they added three different substances to the growing segments:
- DNA extract
- Extract of vascular tissues
- Coconut milk

6. **Observation of Growth**: They noticed that the addition of any of these substances resulted in enhanced growth of the callus. This led them to investigate further.

7. **Identification of Cytokinins**: Upon further analysis, they discovered that all three substances contained a common component, which was identified as cytokinin. This was the breakthrough that led to the isolation of cytokinins.

8. **Conclusion**: Therefore, the scientist who first isolated cytokinin was Skoog and his co-workers.

**Final Answer**: The scientist who first isolated cytokinin was Skoog and his co-workers.

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