OCR A-level biology Microscopes

OCR A-level biology Microscopes


OCR A-level biology Microscopes
What are the 4 types of microscopes? - Light, electron , transmission, laser scanning confocal
microscopes.



What makes a good microscope observation drawing? (8) - 1. Title

2. Magnification of image

3. Scale (can be bar or conversion calculation I.e measurement 33mm magnification x400)

4. No shading

5. Clear continuous lines

6. Label lines straight and no heads

7. Label lines do not cross

8. Label lines parallel to the top of the page



What is a light microscopes source of image? - Light



How is the a light microscopes beams focused? - Lenses



What's the maximum effective magnification of a light microscope? - x1500-2000



What's the maximum resolution of a light microscope? - 200nm



Can live specimens be used on light microscopes? - Yes



Can you see a section or surface of the specimen using a light microscope? - Both



Is a light microscope cheap or expensive? - Cheap



Does a light microscope show you Colour or B&W? - Colour

, OCR A-level biology Microscopes




Is staining of the specimen required in light microscopes? - Yes



What is the source of image in a transmission electron microscope? - Electrons



How is the beam focused on a TEM? - Electromagnets



What is the maximum effective magnification on a TEM? - x 1million



What is the maximum resolution on a TEM? - 0.5nm



Can a live specimen be used on a TEM? - No



Does a TEM show a section or surface of the specimen? - Section



Is a TEM cheap or expensive? - Expensive



Are images produced my TEM B&W or Colour? - B&W



Do you have to stain the specimen on a TEM? - Yes, give it a metal coating



What is the source of image on a scanning electron microscope? - Electrons



How is the beam focused on a SEM? - Electromagnets



What is the maximum effective magnification on a SEM? - x 500,000



What is the maximum resolution on an SEM? - 3-10nm