Key Points
Key Points: Grades of Organization
| No. | Grade of Organization | Description | Examples |
|---|---|---|---|
| 1 | Protoplasmic Grade | All functions performed by a single cell | Amoeba, Paramecium |
| 2 | Cellular Grade | Body made of cells, but tissues not formed | Phylum Porifera (e.g. Sycon) |
| 3 | Cell-Tissue Grade | Cells form tissues to perform functions | Phylum Cnidaria |
| 4 | Tissue-Organ Grade | Tissues form organs, but organ systems not fully developed | Flatworms |
| 5 | Organ-System Grade | Organs work together to form systems with specific functions | Crab, Frog, Human |
