Light Microscopy Flashcards
(20 cards)
What is a tissue?
A collection of cells specialised to perform a particular function.
What is an organ?
An aggregation of tissues with a specific set of functions.
What diameter are most human cells?
10-20 micrometers.
He large are human egg cells?
0.1 mm
How large are human red blood cells?
7.2 micrometers.
What is a biopsy?
The removal of a small piece of tissue from an organ or part of the body for microscopic examination.
What is a smear biopsy used for?
To take a biopsy from the cervix or buccal cavity.
What is a curettage biopsy used for?
Taking a biopsy from the endometrial lining of the uterus.
What is a needle biopsy used for?
To take a biopsy of the brain, breast, liver, kidney or muscle.
What is a direct incision biopsy used for?
To take a biopsy from the skin, mouth or larynx.
What is an endoscopic biopsy used for?
To take a biopsy from the lungs, intestine or bladder.
What are the stages of tissue processing for s biopsy?
Fixation with glutaraldehyde of formaldehyde.
Dehydration with water and ethanol.
Clearing with xylene or toluene and ethanol.
Embedding with wax.
Sectioning using a microtome.
Rehydration with xylene ethanol and water.
Staining.
Dehydration with water ethanol and xylene.
Mounting on a slide using DPX.
What does haematoxylin stain and what colour is it?
Acidic components of cells purple/blue.
E.g. Nucleolus and chromatin.
What does eosin stain and what colour is it?
Stains basic components of cells pink.
E.g. Most cytoplasmic proteins and extracellular fibres.
What does PAS stain and what colour is it?
Carbohydrates and glycoproteins magenta.
What is phase contrast microscopy used for and how does it work?
To view detail in living cells.
It exploits the interference effects produced when two light waves combine.
What is differential-interference-contrast microscopy used for and how does it work?
Used to view detail in living cells. Exploits the interference effects produced when two sets of waves combine.
What is confocal microscopy?
Microscopy used to image tissues labelled wig one or more fluorescent probes. It eliminates out of focus flare from the specimens by scanning the sample in optical sections.
What is darkfield microscopy?
Microscopy which excludes the unscatteree light from around the images so e area around the specimen appears dark.
What is histology?
The study of structures of tissues by means of special staining techniques combined with light and electron microscopy.
