CB1a Microscopes Flashcards
What does a light microscope do?
Use light to magnify objects
Greatest possible magnification with a light microscope?
About x2000
What does an electron microscope do?
Uses electrons to magnify objects
Greatest possible magnification with an electron microscope?
x10 million
Characteristics of an electron microscope
High resolution High magnification Expensive Black and white Three Dimensional
Characteristics of a light microscope
Low resolution
Low magnification
Cheap
Coloured
What is resolution?
Resolution is the smallest distance between two points that they can still be seen as two points
What is magnification?
Magnification is how many times bigger the image is from the original image
How do you calculate magnification?
Magnification = image size / real size
How do you calculate total magnification?
Total Magnification = Objective x Eye Piece
Steps of using a light microscope
- Start with the lowest objective under the eyepiece
- Clip the slide securely on the stage
- Adjust light source so the light goes up through the slide
- Use the coarse focusing wheel to focus the slide
- Move the slide so that the cell you will see is in the middle of the view
- If needed, use a higher objective
- Use fine focusing wheel to bring the cell into focus
Who invented microscopes?
Robert Hooke
What is the ink called to see a colourless object in the microscope?
A stain, such as iodine.
Units of millimetres
mm (10^-3)
Units of micrometers
μm (10^-6)
