Types of Microscopes

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Types of Microscopes
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Types of Microscopes

• Light Microscope what we use in lab
• Uses light to magnify
• Used to look at living cells
• Magnify up to 1500x
• Electron Microscope (1930-1940)
• Uses beams of electrons
• Magnify up to 500,000x
• See inside of cells, look at structures
• 2 types

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Scanning Electron Microscope (SEM)

• Scan surfaces of cells, look at 3D shape

http//www.mos.org/sln/sem/diatom.html
http//mse.iastate.edu/microscopy/whatsem.html
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Transmission Electron Microscope(TEM)

• Look at structures within the cell

http//en.wikipedia.org/wiki/Transmission_electron
_microscope
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New Technology

• New models helpful techniques all the time
• Example Scanning Tunneling Microscope
• Uses flow of electrons to create computer images
  of atoms on the surface of a molecule

www.chem.utoronto.ca/staff/DHIRANI/index.htm
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Cell Theory
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The Cell Theory

• 3 Main Ideas
• All organisms are composed of 1 or more cells.
• The cell is the basic unit of structure
  organization of organisms.
• All cells come from preexisting cells.

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The Cell

• With better microscopes, discovered that cells
  contain small specialized structures called
  organelles
• Each organelle has a specific function within a
  cell

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Types of Cells

• 2 broad groups
• Eukaryotes contain membrane-bounded organelles
• Most multi-cellular organisms some unicellular
  ones, like algae
• Prokaryotes do not
• Example bacteria and other unicellular organisms

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What do they look like?
http//en.wikipedia.org/wiki/Eukaryotic
http//www.earthlife.net/prokaryotes/images/bacter
ia.gif