1. Microscopes Prof.ssa Patrizia Mauri ISISS “Cicognini-Rodari” - Prato

2. The first cells were observed by Robert Hook in 1632. They were cork cells. Then Antony van Leewenhoek observed many other kinds of cells. Obviously their microscopes were very rudimentary.

3. Visualizing Cells

5. Optical Microscope Electron Microscope

7. O.M. Images Paramecium An unicellular alga Blood cells Leaf tissue

9. TEM Transmission Electron Microscope Electrons are transmitted through the specimen to a photographic plate and we can observe the image on a monitor. The specimen has to be cut in very thin sections.

10. TEM Images A mitochondrion HIV- Viruses Muscle fibers Rickettsie

11. SEM Scanning Electron Microscope Electrons bounce onto the surface of the specimen and then are recorded on a photographic plate likewise a photographic scanner. ---> 3D image of cells, structures and surfaces.

12. SEM Images Human blood cells Pollen A lynphocyte HIV- Virus

13. Bacteria An arm hair Sperm cells on an egg RBC inside an artery