Sponges are most primitive multicellular organism with which of the following levels of organization ?

Options

A. Acellular
B. Cellular
C. Tissue
D. Organ system

Answer

To determine the level of organization in sponges, we can follow these steps:

1. **Understanding Levels of Organization**: The levels of biological organization include cellular, tissue, organ, and organ system levels. Each level represents a different complexity in the arrangement of cells.

2. **Identifying Sponges**: Sponges belong to the phylum Porifera. They are known to be the most primitive multicellular organisms.

3. **Analyzing the Options**:
- **A-cellular**: This level refers to organisms that are not made up of cells, which is not applicable to sponges.
- **B-cellular**: This level indicates that the organism is made up of cells but does not have organized tissues. Sponges fit this description as they consist of a loose aggregation of cells.
- **C-tissue**: This level indicates a higher complexity where cells are organized into tissues. This is not applicable to sponges.
- **Organ system**: This level represents a more complex organization found in higher organisms, which sponges do not possess.

4. **Conclusion**: Since sponges are composed of a simple aggregation of cells without organized tissues, they exhibit the cellular level of organization.

5. **Final Answer**: The correct answer is **B-cellular**.