1. Number of Cells:
- Unicellular: Consists of a single cell.
- Multicellular: Composed of many cells working together.
2. Complexity of Structure:
- Unicellular: Simple in structure, all functions performed by a single cell.
- Multicellular: Complex and organized, with specialized cells forming tissues, organs, and organ systems.
3. Life Cycle and Reproduction:
- Unicellular: Often reproduce asexually through processes like binary fission or budding. Life cycle is simple, with a single cell performing all essential functions.
- Multicellular: Typically reproduce sexually, requiring the fusion of gametes. Life cycle is more complex, involving embryonic development and growth.
