Which of the following animals have scattered cells with cell - tissues grade organization ?

Options

A. Sponge
B. Hydra
C. Liver fluke
D. Ascaris

Answer

To determine which of the following animals have scattered cells with cell-tissue grade organization, we need to analyze each option provided:

1. **Understanding Cell-Tissue Grade Organization**:
- Cell-tissue grade organization refers to a level of biological organization where cells are grouped together to perform specific functions, but they are not organized into true tissues. This is typically seen in simpler organisms.

2. **Analyzing the Options**:
- **A. Sponge**: Sponges have a cellular level of organization. Their cells are not organized into true tissues, as they lack specialized cells that perform specific functions collectively. Therefore, sponges do not fit the criteria.
- **B. Hydra**: Hydra is a member of the phylum Cnidaria and exhibits a tissue grade of organization. The cells in Hydra are organized into tissues that perform specific functions, making it a candidate for having scattered cells with cell-tissue grade organization.
- **C. Liver Fluke**: Liver flukes are more complex organisms that have a higher level of organization, specifically an organ-system level. They do not have a cell-tissue grade organization, as their cells are organized into true tissues and organs.
- **D. Ascaris**: Ascaris is a roundworm and also exhibits a higher level of organization (organ-system level). Like the liver fluke, it does not fit the criteria for cell-tissue grade organization.

3. **Conclusion**:
- Based on the analysis, the only organism that fits the description of having scattered cells with cell-tissue grade organization is **B. Hydra**.

**Final Answer**: The correct answer is **B. Hydra**.

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