Microscopy Flashcards
What is a light microscope
Uses and light and lenses to form an imagine of a specimen and magnify it
What is an electron microscope
Uses electrons to form an image. They have a much higher magnification and resolution, lets us see smaller things in detail
What is the formula for magnification
Magnification= image size/real size
Remember image size and real size should have the same units
How do you write small numbers
Standard form
How do you prepare a slide
- You need to put the specimen on a slide
- Add a drop of water to middle of slide
- Cut an onion and separate into layers. Use tweezers to peel off epidermal tissue.
- Place into water on the slide
- Add a drop of iodine situation (stains are used to highlight objects in a cell by adding colour
- Place a cover slip on top (try not to get air bubbles, they’ll obstruct your view)
How do you use a light microscope
- Clip the slide onto the stage
- Select the low/high powered objective lens (magnification)
- Use the coarse adjustment knob to move the stage up below the objective lens
- Look at the eyepiece. Use coarse adjustment knob to move the stage downwards until image is roughly in focus
- Adjust the focus with the fine adjustment knob, until you get a clear image
How to draw observations
Use a sharp pencil
Takes up at least half of space, drawn with clear solid lines
No colouring or shading
Subcellular structures should be drawn in proportion
Write a title of what you’re observing and magnification
Label with straight lines