Key Components:
๐๏ธ Eyepiece (Ocular Lens)
- Usually magnifies ร10
- Where you look through the microscope
- Contains the lens closest to your eye
๐ Objective Lenses
- Usually ร4, ร10, ร40, and ร100
- Different magnifications on rotating nosepiece
- Primary magnification of the specimen
- Always start with lowest power (ร4 or ร10)
๐ Stage
- Platform where specimen slide is placed
- Has clips to hold slide in position
- Some have mechanical stage for precise movement
- Central hole allows light to pass through
๐ก Light Source
- Modern microscopes use LED or halogen bulbs
- Older models may use mirror and external light
- Illuminates specimen from below
- Adjustable brightness
๐๏ธ Focus Controls
- Coarse focus: Large adjustments, low power only
- Fine focus: Precise adjustments, all powers
- Move stage up/down to bring specimen into focus
This key facts covers Light Microscope Structure and Function within Microscopy for GCSE Biology. Light and electron microscopes, magnification and resolution calculations, specimen preparation, staining techniques, and practical microscopy skills It is section 3 of 20 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Microscopy
What is magnification?
Explain why specimens are stained before viewing under a light microscope.
Quick recall flashcards
What is resolution?
Resolution is the ability to distinguish between two separate points that are close together. It determines how clear and detailed an image is.
What is magnification?
Magnification is how many times larger an image appears compared to the actual object. It tells us how much bigger something looks through a microscope.