The scientists who postulated the cell theory were:
-Robert Hook: he was the first scientist to use the word cell, he observed cork and he calls cells the divisions he saw.
- Leeuwenhoek: he built biconvex lenses and with them he observed microorganisms such as bacteria and protozoa and cells such as sperm and red blood cells.
- Schleiden: he studied embryonic cells and discovered the nucleolus