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Microscope Labelling Worksheet

Fourteen parts to label, with an answer key and function questions.

A labelling exercise for the compound microscope. Print or copy the list, have students write the function beside each part from memory, then check against the key.

Students who need the diagram explained before attempting this should read compound microscope parts labeled first.

Part 1 — label these fourteen parts

  1. Eyepiece (ocular lens)
  2. Body tube
  3. Revolving nosepiece
  4. Objective lenses
  5. Arm
  6. Stage
  7. Stage clips
  8. Mechanical stage control
  9. Condenser
  10. Iris diaphragm
  11. Illuminator
  12. Base
  13. Coarse adjustment knob
  14. Fine adjustment knob

Part 2 — answer key

PartFunction
EyepieceMagnifies the objective's image, usually 10×
Body tubeHolds the correct optical distance between lens systems
Revolving nosepieceRotates objectives into the light path
Objective lensesForm the magnified real image; set resolution
ArmSupports the tube; the correct carrying point
StagePlatform supporting the slide
Stage clipsHold the slide in position
Mechanical stage controlMoves the slide precisely on two axes
CondenserFocuses light into a cone at the specimen
Iris diaphragmSets the width of the illuminating cone — contrast
IlluminatorLight source
BaseSupports the instrument
Coarse adjustmentLarge focus movement, low power only
Fine adjustmentSmall focus movement, required above 100×

Part 3 — short answer

  1. A 40× objective with a 10× eyepiece gives what total magnification?
  2. Why must coarse focus not be used with the 40× objective?
  3. Which control adjusts contrast, and which adjusts brightness?
  4. Why does the 100× objective require immersion oil?
  5. Give one specimen suited to brightfield and one that needs phase contrast.