Understanding Microscopes and Cell Size Calculations

This detailed page covers the essential aspects of microscopy and cell size calculations, presenting a comprehensive comparison between electron and light microscopes alongside practical measurement techniques.

Definition: Magnification is the process of making something appear larger than it is, calculated by dividing image size by actual size.

Highlight: The total magnification of a microscope is calculated by multiplying the objective lens magnification by the eyepiece magnification.

The key differences between microscope types are explained:

Light Microscope:

• Uses light to form images
• Can view living samples
• Relatively inexpensive
• Lower magnification and resolution

Electron Microscope:

• Uses electron beams
• Cannot view living samples
• More expensive
• Higher magnification and resolution

Example: A practical calculation demonstrates finding actual cell size:

• Image size: 15mm
• Objective lens magnification: 40x
• Eyepiece magnification: 10x
• Total magnification: 400x
• Actual size calculation: 15/400 = 0.0375mm = 3.75 × 10⁻² mm

Vocabulary:

• Objective lens: The primary magnifying lens closest to the specimen
• Eyepiece: The lens through which the observer views the specimen
• Standard form: Scientific notation used to express very large or small numbers

The page also includes a detailed diagram of a compound microscope, labeling essential components such as the stage, coarse focus, fine focus, and condenser.