Agricultural Biology Mr. Bushman Microscope Unit Agricultural Biology Mr. Bushman

Functions of Microscope Parts Arm: Basic frame, used to carry microscope. Base: Bottom stand, which houses the light. Body: Contains mirrors to reflect light to eyepiece. BASE BODY ARM

Functions of Microscope Parts Coarse Adjustment: Roughly focuses image by bringing the specimen and objective lenses closer together or farther apart. Fine Adjustment: Sharpens image of specimen by moving specimen and objective lenses very small distances closer together or farther apart. BASE BODY ARM COARSE ADJUSTMENT FINE ADJUSTMENT

Functions of Microscope Parts Diaphragm: Disc-shaped device, located beneath stage, used to control amount of light passing through specimen. Eyepiece: Upper lens, nearest your eye, which magnifies image already magnified by objective and brings light rays to a focus at the eye. BASE BODY ARM COARSE ADJUSTMENT FINE ADJUSTMENT EYEPIECE DIAPHRAGM

Functions of Microscope Parts Light: Source of light which passes through specimen. Nosepiece: Revolving part that supports three objectives with different magnifications. BASE BODY ARM COARSE ADJUSTMENT FINE ADJUSTMENT EYEPIECE DIAPHRAGM LIGHT NOSEPIECE

Functions of Microscope Parts BASE BODY ARM COARSE ADJUSTMENT FINE ADJUSTMENT EYEPIECE DIAPHRAGM LIGHT NOSEPIECE OBJECTIVE STAGE CLIPS STAGE Objective: Lens closest to specimen, that magnifies image of specimen. Stage: Flat table-like area where slide or specimen is placed. Stage Clips: Hold slide on stage, to prevent it from slipping around.

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Microscopic Terms

Microscopic Terms Slide: Piece of glass upon which specimen is placed for viewing. Cover Slip: Thin square piece of glass or plastic used to cover specimen.

Microscopic Terms Magnification: Number of times an object’s apparent size is increase by lens system. Total magnification = power of objective x power of eyepiece (usually 10x). Total magnification of lens system is determined by multiplying power of objective times power of eyepiece (usually 10x).

Microscopic Terms High Power: The high power objective on the nosepiece (usually 40x). Medium Power: The middle power objective on the nosepiece (usually 10x). Low Power: The lowest power objective on the nosepiece (usually 4x).

Microscopic Terms Resolution: Ability of lens system to distinguish and separate fine details in a specimen. Field of View: Area of specimen which is seen through lens system; bright circle you see when looking into a microscope.

Microscopic Terms Depth of Field: Ability of a lens system to furnish a distinct image above and below focal plane. Depth of focus decreases with increase of magnification. Parfocal: When objective is in focus, it can be switched from one power to another, with only small fine focus adjustments being necessary.

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Use of the Microscope

Use of the Microscope 1. Carry with both hands. 2. Set microscope in from edge of desk. 3. Use lens paper to clean eyepiece and objectives. 4. Start with lowest power (shortest objective) in place.

Use of the Microscope 5. Turn coarse adjustment so that stage is as close to low power as possible -- now while looking, turn coarse adjustment so stage starts to move away from objective. 6. Clean up all spills and moisture from stage before putting away.

Use of the Microscope 7. Caution – Keep all water away from electrical parts 8. Never use coarse adjustment with high power objective while trying to focus, because of danger of striking and breaking glass slide with objective.

Types of Microscopes Light Microscope Electron Microscope Source: Light Magnifies by using glass lenses Magnifies up to 2000 times Materials can be living or dead Electron Microscope Source: Electrons Magnifies by using magnets Magnifies up to 2 million times Materials are dead

OH NO IM Next I don’t like shots! HA HA