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Types of Microscopes. 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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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
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
Transmission Electron Microscope(TEM) • Look at structures within the cell http://en.wikipedia.org/wiki/Transmission_electron_microscope
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
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.
The Cell: • With better microscopes, discovered that cells contain small specialized structures called organelles • Each organelle has a specific function within a cell
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
What do they look like? http://en.wikipedia.org/wiki/Eukaryotic http://www.earthlife.net/prokaryotes/images/bacteria.gif