Who is called father of plant physiology?

Options

A. Calvin
B. J.C.Bose
C. Stephen Hales
D. Van Helmont

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for the individual who is recognized as the "father of plant physiology."

2. **Define Plant Physiology**: Plant physiology is a branch of biology that deals with the functions and processes of plants. It encompasses various aspects of plant life, including growth, metabolism, and responses to environmental stimuli.

3. **Identify Key Figures**: The question provides multiple options, including Calvin, Jesse, Stephen, and Van Helmont. We need to determine which of these individuals is credited with foundational contributions to plant physiology.

4. **Research Historical Contributions**:
- Stephen Hales is known for his pioneering experiments in the early 18th century, particularly in 1727, where he conducted extensive studies on plant functions, including the measurement of plant transpiration and the role of water in plants.
- Julius von Sachs later contributed to the field by unifying various aspects of plant physiology, but he is not referred to as the father of the discipline.

5. **Conclude the Answer**: Based on historical contributions, Stephen Hales is recognized as the father of plant physiology due to his significant experimental work in the field.

6. **Select the Correct Option**: The correct answer is option number 3, Stephen Hales.

**Final Answer**: Stephen Hales is called the father of plant physiology.

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