Cells

1. Beam of electrons fired through specimen - Specimen must be thin and stained using electron dense substance - Electron dense substance deflects electrons in beam and pattern remaining e- produce as they pass through specimen is converted to image. (3)
4. False images arising from poor technique. (9)
5. The basic units of living organisms. (5)
6. Light rays focused by lenses. (5, 10)
7. Minimum distance apart 2 objects must be in order for them to appear as separate items. (9, 5)

2. The ability to distinguish between 2 close objects. (10)
3. Beam of electrons focused by electromagnets. (8, 10)
8. Specimen coated with thin film of heavy metal - Electron beam scanned to and fro across specimen - Electrons that are reflected from surface are collected and produce image on viewing screen. (3)
9. Form vast majority of living organisms including plant and animal cells. (10)
10. Very small single celled organism, no nucleus and no membrane-bound organelles. (8)

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