Cytology Flashcards
What is cytology?
The study of cells in terms of structure, function and chemistry
What is histology?
The study of the fine detail of cells and tissues using microscopes
What are the three principles of cell theory?
- Cells are membrane enclosed units and are the basic unit of life
- All living things are made up of cells
- All cells come from other cells
What is magnification?
The ratio of image size to object size
What is resolution?
The ability to distinguish separate images of closely positioned objects
Why is resolution important?
Without high resolution magnification is useless
What is the magnification on light microscopy?
1000x
What is the resolution on light microscopy?
2nm/200nm
What is fluorescence microscopy?
The use of fluorescence dyes to highlight specific structures/molecules light passes through 2 sets of filters
What does the first filter in fluorescence microscopy do?
Allows only wavelengths to pass that excites the specific dye
What does the second filter in fluorescence microscopy do?
Allows only those wavelengths that are emitted by specific dye
What is confocal microscopy?
Specialised fluorescence microscope creating optical sections that can be combined to create a 3D image
What is transmission electron microscopy?
Beam of electrons used instead of beam of lights, specialised specimen preparation
What is the magnification of transmission electron microscopy?
1000000x
What is the resolution of transmission electron microscopy?
1nm
How does scanning electron microscopy work?
A specimen coated with a thin layer of heavy metal is scanned by beams of electrons creating a 3D image
What is the resolution of scanning electron microscopy?
3nm-20nm
What are the four types of tissue?
Epithelia
Connective tissue
Muscle tissue
Nervous tissue
What is epithelial tissue?
Closely adherent cells found on surfaces
What is columnar epithelial cells?
Long cells tightly packed together nucleus in line close to the basal laminar
What is squamous epithelial cells?
Uneven single layer of cells
What is cuboidal epithelial cells?
Single layer of cuboidal cells
What is stratified epithelial cells?
Multiple cells on top of each other
What is the apical surface?
The surface of the epithelial sheet that is facing the air
