Branched veins with flowing protoplasm occur in

Options

A. (a) acellular slime moulds
B. (b) cellular slime moulds
C. (c) euglenoids
D. (d) dinoflagellates

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the occurrence of branched veins with flowing protoplasm. This is a characteristic feature of certain types of organisms.

2. **Identifying the Options**: The options provided are:
- a. Acellular slime molds
- b. Cellular slime molds
- c. Euglenoids
- d. Dinoflagellates

3. **Analyzing Acellular and Cellular Slime Molds**:
- Acellular slime molds (also known as plasmodial slime molds) have a multinucleate structure and are typically in a diploid stage. They exhibit flowing protoplasm and can form branched structures.
- Cellular slime molds, on the other hand, exist in a haploid stage and are composed of individual cells that can aggregate but do not form branched veins with flowing protoplasm.

4. **Examining the Characteristics of Other Options**:
- Euglenoids are unicellular organisms that have a flagellum and are known for their photosynthetic capabilities but do not have branched veins with flowing protoplasm.
- Dinoflagellates are also unicellular and are characterized by their two flagella and armored plates, but they do not exhibit the feature of branched veins with flowing protoplasm.

5. **Conclusion**: Based on the analysis, the only option that fits the description of having branched veins with flowing protoplasm is **Acellular slime molds**.

**Final Answer**: The correct answer is **a. Acellular slime molds**.

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