Introduction To Histology Flashcards
Deals with the physiologic structure and function of human cells and tissues. it is also known as microscopic anatomy or micro anatomy
Human histology
Histology is the microscopic counterpart for gross anatomy where it focuses on larger structures visible without the use of a microscope
True
Treatment of tissue with chemical
Fixation
Removal of water from the tissue sample
Dehydration and clearing
Infiltration of tissue sample with paraffin
Embedding
Cutting tissue sample bisection into specific equal increments
Sectioning
Placing the tissue sample on adhesive glass slides
Mounting and staining
Fixation
10% formaldehyde solution uses:
-Preserves the tissues structure
-prevents enzymatic degradation of cells and tissues by autolysis
-kills pathogenic microorganisms
- hardens tissue for histopath exam
Other fixatives
•Zenker’s - w/ mercuric chloride, for lm, excellent fixative
•Bouin’s- w/ picric acid, testicular biopsies
•Carnoy’s- w/ ethanol, chloroform & glacial acetic acid, dissolves fat
Dehydration
Specimens dehydrated in a series of increasing alcohol solutions 70% 80% 95%
Clearing
Removes the alcohol solution (xylene chloroform)
Evens out the wax or paraffin embedded tissue using a sharp knife before sectioning is done
Trimming
Commonly used stains
Hematoxylin
eosin
toluidine blue
Forms the basophilic components of the cell
Hematoxolin
Forms the acidophilic components of the cell
Eosin
Forms the metachromic component of the cell
Toluidine blue
Very good staining procedure for histology specimens for it displays the structural features of cells and tissues
Does not adequately reveal structural components of lipids basement membrane and reticular fibers
Hematoxylin and eosin
Carries a net negative charge on its colored portion
Result: orange, red, dark pink
Acidic dye
Stains under acidic dye
Acid fuschin
eosin
orange g
Carries a net positive charge on its colored portion
Results: blue, purple, green
Basic dye
Examples of basic dye stain
Methylene blue
toluidine blue
hematoxylin
This is a special stains for glycogen, fungi and parasites
Periodic acid schiff (PAS)
Acid fast org
Ziehl- Neelsen
“fungi & pneumocystis”
Grocott’s
Fungi, amoeba, trichomonas
PAS
Helicobacter etc.
Dieterle
Neuroendocrine cells
Argentaffin stains
Amyloid
Congo red stain
Connective tissue & basement membrane
Reticulin stain
Melanin
Fontanna masson
Lipids
Oil red o
Histopath procedure wherein instant pato disease is needed by surgeon
Frozen sections
The specificity of a reaction between an antigen and an antibody
- uses fluorescent dyes
Immunocytochemistry (IHC)
Glycoproteins that are produced by specific cells of the immune system in response to a foreign protein
Antibody “immunoglobulins”
Foreign protein at which antibody reacts
Antigen
Are chemicals that absorb light of different wavelengths example uv light
Fluorescent dyes
Method used in the study of cells and its structure using microscope
Microscopy
Major kind of microscope that utilizes light for elimination
Light microscope
Major kind of microscope uses an electron beam
Electron microscope
H
It’s a part of a microscope in which the image formed by the objective lens may be directly examined
Ocular lens
Gather the light that has passed through the specimen it has
Objective lens
To focus the beam of light at the specimen
Condenser lens
On which the slide is placed
Stage
Controls the movement of the stage for proper focusing
Stage control
Uses the fine power objective and course power objective
Focusing control
Focuses the light being from the light source to the condenser
Field diaphragm
For specimen illumination
Light source
It is the ratio between the size of an image produced by the microscope and its actual size
Magnification
A measure of clarity of an image
Resolution
The ability to visualize a particular cell structure depending on how different it looks from an adjacent structure
Contrast
