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.
