Download microscopy

Studying the Structure of Cells
1.1
The Cell Theory
• All living organisms are made of one or more
cells.
• The cell is the basic organizational unit of life.
• All cells come from previously existing cells.
Cell Organelles
Plant Cell Organelles
Microscopes
• The Leeuwenhoek
microscope from the
1600s could magnify
specimens up to 250x.
• There have been many
developments in
microscopy since.
Brightfield/Darkfield Microscope
• Up to 2000x
• Thin metal disk beneath
stage converts
brightfield to darkfield,
making details more
visible.
Fluorescence Microscope
• Up to 1500x
• Specimen is treated
with fluorescent stains
to make certain cell
structures or
substances glow.
Transmission Electron Microscope
• Up to 1 000 000 x
• Aims a beam of
electrons through a
specimen.
• Denser parts of the
specimen let less
electrons through.
Scanning Electron Microscope
• Up to 200 000 x
• Sweeps a beam of
electrons across the
surface of the
specimen, producing a
3-D image.
Phase-Contrast Microscope
• Up to 1500x
• Images produced by
differences in
specimen’s ability to
refract light.
• Good for viewing living
cells.
Compound Light Microscope
• Up to 1000x (ours 400x)
• This is the kind of
microscope we will be
using in class.
• Two lenses increase the
total magnification.
• This video from 1948 (!)
shows the parts & how
to use.
Parts of the Microscope