Parts of a Microscope Microscope Basics. Label the Compound Light Microscope (Handout) Ocular lens...
-
Upload
milton-thomas-hodge -
Category
Documents
-
view
217 -
download
0
Transcript of Parts of a Microscope Microscope Basics. Label the Compound Light Microscope (Handout) Ocular lens...
Parts of a Microscope
Microscope Basics
Label the Compound Light Microscope(Handout)
Ocular lens
Body TubeCoarse Adjustment KnobFine adjustment KnobRevolving nosepieceObjective lenses (4x, 10x, 40x)ArmStage Stage ClipsDiaphramLight source
Base
Taking a look at the world…. Look around the room….What types of things can you see in plain view (with your eyes)?
Now, use the hand-held magnifying glass….What new things can you see?
What types of things might you see if these things were magnified, 10x, 40x, 100x, 10 000x or even 1 000 000x?
Field of view and Magnification
Microscope History and Development
Microscope HistoryAnton Van Leeuwenhoek
The father of microscopyfirst to see and describe bacteria.
Robert HookeRobert Hooke: sees cork through a
microscope lens and noticed some "pores" or "cells" in it.
First person to use the word "cell”
Technological Advances in Microscopes
Compound Light Microscope
• Uses light• Has two lenses• Magnification is limited to 2000x• We use this type at LHHS (our
magnification is 400x)
Transmission Electron Microscope (TEM)
Uses beams of electronsMagnification of 2 000 000xHas two limitations:
Good only for thin specimensOnly dead cells can be observed
Scanning Electron Microscope (SEM)
Electrons are reflected from the surface of the specimen
Produces a 3-d imageGood for the thicker specimensLacks the magnification and resolution of the
transmission electron microscope
SEM
Guess the Picture: These are images using a SEM microscope!• Cat flea
SEM
• Mosquito head
SEM
• Porcupine Quill
SEM
• Toilet Paper
SEM
• Mascara Brush
SEM
• Mosquito Head Close-up
SEM
• Foot of a house fly
SEM
• Dentist Drill
SEM
• Velcro
MagnificationMagnification = Objective lens X
Ocular lens(4x, 10x, 40x)
(10x)
Calculating the size of a specimenbinder
Calculating the size of a specimenExample under med. objective
Object size = Size of field of viewNumber of objects across field of view
Object size = 1.72 mm 14
Object size = 0.1 mm