Histotechniques and Lab Safety Flashcards
What level biohazard is the laboratory?
Level 2
What is one of the most important means of preventing the spread of infection?
hand hygiene
How long do you flush your eyes at the eye wash station?
15 minutes
What does PASS stand for referring to the fire extinguisher?
Pull the pin - Aim at the fire - Sweep - Side to side
How do you calculate total magnification?
magnification of ocular (10x) x magnification of objective
What connects the eyepieces with the objective lens?
optical tube/body tube
What contains the housing for the fine and coarse adjustments?
arm
What is the rotating wheel on the underside of the stage that allows the adjustment of the amount of light?
light diaphragm
What gathers the light from the microscope and concentrates it?
condenser
What is the distance between the centers of your two pupils?
interpupillary distance
What are the four advantages of Koehler illumination?
even illumination, highest contrast and resolution, reduced specimen heating, eliminates reflection and glare
What are the 6 histotechniques?
surgical removal of tissue, fixation, tissue processing, embedding, sectioning, staining
What are the three steps in tissue processing?
dehydration, clearing, wax infiltration
What chemical do they use to dehydrate the tissue?
ethyl alcohol
What do they replace the alcohol with during clearing?
xylene
How thin does the microtome cut the tissue?
4-6 um
What stains the nuclei blue?
hematoxylin
What stains the cytoplasmic content pink?
eosin
What are some tissues derived from the ectoderm (outer layer)?
epidermis, epithelium of nasal cavities, sinuses, mouth, nervous system, posterior pituitary gland
What are the tissues derived from the mesoderm (middle)?
muscle, connective tissue, epithelium of blood vessels, kidney, adrenal, etc.
What is the microscopic study of the form and structure of NORMAL tissue?
histology
What is the microscopic study of changes in diseases tissues?
pathology
What is histotechnology?
the preparation of tissues for microscopic examination
What are curettings?
scrapings
How do they accession specimens for identification?
lab pathology number
What are the pieces of dissected tissue placed in?
small plastic cassettes
how is the kidney cut?
BIsected
how is the spleen cut?
several times
How long are species preserved in formalin?
approximately 3 months
What is the preservative used for fixation?
10% neutral buffer formalin
What is the decomposition of tissue by bacteria, fungi, or viruses?
putrefaction
What are the two methods of fixation?
physical (freezing), chemical (fluid fixative)
What is the aim of tissue processing?
to make fixed tissues ready for cutting into thin sections
How long does typical tissue processing take?
over 15 hours (4:30pm - 7am)
What is the job of paraffin wax?
to fill all the spaces within the tissue so that cellular components are adequately supported
Which stain is basophilic?
blue - hematoxylin
What are the three stages of staining tissues?
dewaxing, staining, permanent preparation (mount)
