Which one of the following theory in root is equivalent to Schmidt's theory ?

Options

A. Tunica corpus theory
B. Histogen theory
C. Korper-keppe theory
D. Quiescent center theory

Answer

To answer the question, "Which one of the following theories in root is equivalent to Schmidt's theory?" we need to analyze the theories mentioned and their relation to Schmidt's (Schemendritz's) theory, which is known as the Tunica-Corpus theory.

### Step-by-Step Solution:

1. **Understand Schmidt's Theory**: Schmidt's theory, also known as the Tunica-Corpus theory, was proposed by the scientist Schemendritz in 1924. This theory describes the structure of the shoot apex, which consists of two zones: the Tunica and the Corpus.

2. **Define the Tunica and Corpus**:
- **Tunica**: This is the outer layer, composed of a single layer of small cells. It undergoes anticlinal divisions, which means the cells divide perpendicular to the surface, contributing to surface growth.
- **Corpus**: This is the inner region, which consists of larger cells and undergoes both periclinal (parallel to the surface) and anticlinal divisions, contributing to volume growth.

3. **Evaluate the Options**:
- **Option 1**: Histogen Theory - This theory talks about three histogen layers and is not equivalent to Schmidt's theory.
- **Option 2**: Koper-Cape Theory - This theory describes two zones similar to the Tunica-Corpus theory, making it a potential equivalent.
- **Option 3**: Quiescent Center Theory - This theory describes a specific region in the root apex and does not relate to Schmidt's theory.

4. **Identify the Correct Answer**: Upon evaluation, the Koper-Cape theory aligns closely with Schmidt's Tunica-Corpus theory as both describe two distinct zones in their respective structures.

5. **Conclusion**: The theory in root that is equivalent to Schmidt's theory is the **Koper-Cape Theory**.

### Final Answer:
The Koper-Cape Theory is equivalent to Schmidt's (Schemendritz's) Tunica-Corpus theory.

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