In case of plants or microbes morphology refers to the study of  

Options

A. form or externally visible features
B. form or internally visible features
C. structure and microscopic features
D. none of these

Answer

**Step-by-Step Solution:**

1. **Understanding Morphology:**
- Morphology is a branch of biology that deals with the study of the form and structure of organisms. It includes the examination of both external and internal features.

2. **Morphology in Plants:**
- In the context of plants, morphology is referred to as phytomorphology. This involves studying the physical appearance and external structure of plants.
- Key aspects include the shape, size, color, and arrangement of various plant parts such as leaves, stems, and flowers.

3. **Importance of Plant Morphology:**
- Plant morphology helps in understanding the function of different plant parts and is crucial for biological classification.
- Historically, plants were classified based on their morphological characteristics.

4. **Morphology in Microbes:**
- For microbes, morphology refers to the study of their appearance on growth media, as they are microscopic and cannot be observed directly with the naked eye.
- Microbial morphology involves examining characteristics such as colony size, shape, texture, color, and any odors produced.

5. **Distinction Between Morphology and Anatomy:**
- It is important to distinguish morphology from anatomy. While morphology focuses on external features, anatomy deals with internal structures and microscopic features.

6. **Conclusion:**
- Therefore, in the case of plants or microbes, morphology refers to the study of their external structures and visible characteristics.

**Final Answer:**
In case of plants or microbes, morphology refers to the study of their external structures and visible characteristics.

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