The Microscope

Microscopes

• Most important tool for biologists

• Types: Dissecting Microscope, Light Microscope, &

Electron Microscope

What does a microscope do?

• Enlarges specimens so we can see details

How does it work?

• Light is shined through the (stained) specimen and is magnified with various lenses

Compound Light Microscope Structures

Ocular Lens (eyepiece) Topmost lens through which an object is viewed.

Usually 10x magnification

Structures …

Revolving Nosepiece Rotating piece below the ocular lens that hold the objective lenses

Structures …

Arm Supports the upper

parts of the microscope and provides a carrying handle

Structures …Objective lenses:Scanning objective holds 4X lens used to

view the whole slide.Lower Power Objective holds 10X lens used to

view the object in greater detail

Higher Power Objective holds 40X lens used to

view the object in even greater detail

Magnification

• To find the total magnification you must multiply the ocular lens by the objective lens you are using

For example: 10x X 40x

has a total magnification

of 400X

Structures …

Coarse Adjustment Knob – used to bring an object into approximate focus

used ONLY with scanning objective!

Structures …

Fine Adjustment Knob used to bring object into final focus

Used ONLY with Lower & High Powered Objectives!

Structures …

Diaphragm Controls the amount of light used to view the object

Structures …

Light SourceA lamp that directs a beam of light up through the objective

Structures …

BaseFlat surface of the microscope that rests on the lab table

Also used for carrying the microscope, along with the arm

Structures …

StageHolds and supports microscope slides

Structures …

Stage clipsHolds microscope slides in place