= a beam of electrons with a wavelength of less than 1nm to illuminate specimen.
more detail of cell ultrastructure can been see because electrons have a much smaller wavelength than light waves.
expensive
specimens have to be dead.
vacuum is required.
black and white images are produced.
higher magnification and resolution.
transmission electron microscope
= beam of electrons transmitted through a specimens and focused to produce an image. 0.5nm.
scanning electron microscope
= beam of electrons sent across the surface of a specimen and reflected electrons are collected. 3-10nm.
Resolution not as good as transmission.
3D images produced.
laser scanning confocal microscope
= moves a single spot of focused light across a specimen. Causes fluorescence from the components with dye. Emitted light from specimen is filtered through the pinhole aperture. Only light radiated from very close to focal plane.
thin specimens used.
can be used to see disruption of molecules within a cell.
