Medical applications of processing Flashcards
What are the seven steps of tissue processing?
- Fixation
- Dehydration
- Clearing
- Embedding
- Sectioning
- Mounting
- Staining
What is the chemical used in fixation? What does it do?
Formalin or glutaraldehyde
Preserves, fixates, and renders structure resistant to further processing
What is the chemical used in dehydration? What does it do?
Graded series of EtOH
Removes water from tissue specimen
What is the chemical used in clearing? What does it do?
Xylene
Prepares the tissue for embedding medium
What is done in sectioning?
Cut tissue into thin slices
What is done in mounting?
Place cut section on a slide
What is the chemical used in staining? Why is staining performed?
Various chemicals are used.
Imparts contrast to tissue so that they can be distinguished
What is the chemical used in embedding? What does it do?
Paraffin invades tissues, making them hard and section-able
What is the charge of acid dyes? What structure does this bind to?
negative
mito
What is the charge of basic dyes? What structure does this bind to?
Positive
Nucleus
What is eosin?
Acidic, red dye
What is hematoxylin?
Basic, blue dye
What is metachromasia?
is a phenomeonon in which a given stain imparts different colors to the tissue (based on density, and wavelength changes)
What is the term that describes cellular structures that have a net positive charge? Negative?
Acidophilic
Basophilic
What is the structure affinity (4) and color imparted for hematoxylin?
Nucleus RNA, DNA, ribosomes, a rER
blue
What is the structure affinity (5) and color imparted for eosin?
Secretory vesicles, sER, lysosomes, mitochondria, type I collagen
pink
What is the structure affinity and color imparted for feulgen reaction?
DNA magenta
What is the structure affinity (4) and color imparted for Mallory triple?
Nuceli (red)
muscle (red/orange)
collagen (blue)
Hyaline cartilage (blue)
What is the structure affinity and color imparted for the PAS reaction?
Carbs
Magenta
What is the structure affinity and color imparted for the osmic reaction?
Lipids
Black
What is the structure affinity and color imparted for verhoeff?
Elastic fibers
black
What is the structure affinity (3) and color imparted for silver methods?
Intermediate filaments of nerve cells, glial cells, and reticular fibers
Black
What is the structure affinity and color imparted for trypan blue?
macrophages
Blue
What is the structure affinity and color imparted for prussian blue?
Hemosiderin (ferric Fe)
Blue
What is the structure affinity and color imparted for Nissl?
Ribosomes
Blue
What is the structure affinity (5) and color imparted for Iron hematoxylin?
Nuclear elements, chromosomes, mitochondria, centrioles, and muscle striation
Dark blue/black