Ch. 1 Methods (E1) Flashcards
List the 10 levels of organismal organization.
1) Whole organism
2) Organ system
3) Organs
4) Tissues
5) Cells
6) Organlles
7) Supramolecular assemblies
8) Macromolecules
9) Building block molecules
10) Atoms/ions
List the 4 anatomical sciences.
1) Gross anatomy
2) Histology
3) Embryology
4) Neuroanatomy
The scientific study of microscopic structures of tissues and organs of the body.
What is histology?
What is another name for histology?
Microscopic anatomy (microanatomy)
Today, students in histology laboratories use either {…} or {…} microscopes.
1) Light
2) Virtual
In the past, a more detailed interpretation of microscopic structures was done with the {…} microscope (EM).
Electron
What were the 2 types of electron microscopes used in the past for histology?
1) Transmission electron microscope (TEM)
2) Scanning electron microscope (SEM)
Now, the {…} (AFM) and a variety of {…} microscopic techniques can provide images that are comparable or higher (e.g., AFM) in resolution to those obtained with the TEM.
NOTE: 1st blank is 3 words
1) Atomic force microscopy
2) Super-resolution
What are the 3 steps for tissue preparation?
1) Formalin fixation
2) Paraffin embedding
3) Hemotoxylin & eosin (H&E) staining
The use of a chemical or chemical mixture to permanently preserve the tissue structure for subsequent treatments.
What is fixation?
When should tissue specimens be fixed?
As soon as they are removed from the body
What are the 4 reasons for sample fixation?
1) Terminate cell metabolism
2) Prevent enzymatic degradation
3) Kill pathogenic microbes
4) Harden tissue
This commonly used fixative is a 37% aqueous solution of formaldehyde.
What is formalin?
What is the purpose of embedding a specimen in paraffin?
To permit sectioning (i.e., allowing the specimen to be thinly sliced)
What are the 4 steps of paraffin embedding?
1) Washing specimen after fixation
2) Dehydrating specimen in series of alcohols
3) Clearing out the alcohol using organic solvents
4) Infiltration in melted paraffin
The specially designed slicing machine used to slice the hardened paraffin blocks into sections for slide mounting.
What is a microtome?
A solution that hardens into a permanent mount that keeps the specimen attached to the glass and prevents deterioration of the specimen over time.
What is a mounting medium?
Why must paraffin sections be washed in organic solvents before staining?
Paraffin sections are colorless, thus making them unsuitable for light microscopic examination
What are the 5 steps to staining a tissue section?
1) Dissolve the paraffin w/ organic solvents
2) Rehydrate slide via a series of alcohol solutions in descending concentration
3) Stain w/ hematoxylin in water
4) Dehydrate slide with alcohol solutions in ascending order
5) Stain with eosin in alcohol
Under what 2 conditions might a surgeon request a frozen section?
1) No pre-op diagnosis available
2) Unexpected intraoperative findings
What are the 3 main steps in frozen-section preparation?
1) Freezing the sample tissue
2) Sectioning the frozen tissue
3) Staining the cut sections
What are the 3 most commonly used stains for frozen sections?
1) Hematoxylin & eosin (H&E)
2) Methylene blue
3) Periodic acid-Schiff (PAS)
What are the 3 facets on which histochemical and cytochemical procedures are based?
1) Specific binding of a dye
2) Use of fluorescent dye-labeled antibody of a particular cell component
3) Inherent enzymatic activity of cell component
A process used to localize large molecules present in cells by incorporating radiolabeled precursors into cells and tissues before fixation.
What is autoradiography?