Microscopy

Question 1

what are the differences between light and electron microscopes

Answer 1

• electron microscopes are more expensive
• electron microscopes have higher magnification and resolution
• electron microscopes uses beams of electrons to form an image, light microscopes uses light
• electron microscopes are larger in size

Question 2

equation for magnification

Answer 2

image size / real size

Question 3

how do you prepare a microscope slide

Answer 3

• use a pipette to add a drop of water to the microscope slide
• use forceps to peel a thin layer of epidermal tissue from the inside of an onion
• place the tissue on the slide
• add a drop of iodine to the slide
• lower a cover slip onto the slide, make sure there’s no air bubbles
• use blotting paper to absorb any excess water or iodine

Question 4

how do you use a light microscope

Answer 4

• plug microscope in, turn the light on
• place prepared slide onto the stage, secure with clips
• turn the objective lens to the lowest magnification
• use coarse adjustment knob to move the stage with the slide below the objective lens
• looking through the eyepiece, use the coarse adjustment knob to move the stage down into focus
• use fine adjustment knob to bring the image into clearer focus
• turn to a higher magnification objective lens and refocus slide with fine adjustment knob