The Microscope Flashcards
What is microscopy?
The use of a microscope to visually enlarge objects too small to be visualized with the naked eye.
Who coined the term microscope?
Johannes Faber in 1628.
What are the key purposes of microscopy?
- Visualize cells and tissue
- Identify abnormalities
- Diagnose medical conditions
- Study tissue changes
What does good resolution in a microscope refer to?
The ability to differentiate two lines or points in an object.
What is good contrast in microscopy?
Increased visibility of structures when stains bind to the cells.
What does good magnification allow in microscopy?
The ability to make small objects appear larger.
What are the main parts of a microscope?
- Body tube
- Revolving nosepiece
- Objectives
- Stage clips
- Diaphragm
- Light source
- Ocular lens
- Arm
- Stage
- Coarse adjustment knob
- Fine focus
- Base
- Rheostat
- Interpupillary distance adjuster
What is a compound microscope?
The most commonly used microscope with a condenser beneath the stage that focuses light directly.
What characterizes a bright field microscope?
The specimen is dark and contrasted by the surrounding bright viewing field.
What is the purpose of a dark field microscope?
To identify living, untainted cells and thin bacteria like spirochetes.
How does a phase contrast microscope work?
It uses light passing through a cell with variations in density and refractive index to create contrast.
What is the function of a fluorescence microscope?
It uses UV light for illumination and involves the absorption and re-radiation of light by specimens stained with fluorescent dye.
What does an electron microscope use to create an image?
An electron beam with electromagnets acting as lenses.
What is the limit of resolution for an electron microscope?
Theoretically down to 0.1 nm, realistically down to 2 nm.
What is the first step when using a microscope?
Carry the microscope properly.
When should you use the coarse focus knob?
Only with the 4X objective in place.
What should you do with the microscope after use?
Clean it and return it to the correct cabinet.
What should you avoid touching on a microscope?
The optical lenses with bare hands.
What is a common troubleshooting step if the bulb doesn’t light?
Check the power supply and whether the bulb is blown.
Fill in the blank: A microscope should always be covered to avoid _______.
dust.
What should be done before putting the microscope away?
Turn off the light and wrap the cord correctly.
