Differential staining and blood smears Flashcards
Name the stages of preparing a temporary slide
Fixation, staining, mounting
Name the stages of preparing a permanent slide
Fixation, dehydration, clearing, embedding, sectioning, staining, mounting
What is the advantage of preparing temporary slides?
Rapid and simple
Describe fixation (temporary)
Add 70% alcohol
Why is a specimen covered using a thin glass coverslip?
Exclude dust and air and protect the high power objective lens on the microscope
Why might a specimen be mounted in glycerine after staining?
To stop the specimen from drying out so it can be observed for a longer period of time.
Define differential staining
A staining process which uses more than one chemical stain.
Give 3 advantages of using a preserved form of a specimen.
Enables specimen to be cut into sections, can be treated with a variety of stains, reveals different structures within the tissues and cells.
Longitudinal section (area)
Vertical cut (length x width)
Transverse section (area)
Horizontal cut (pi r2)
Oblique section (area)
Diagonal cut (pi r1 r2)
Is eosin temporary or permanent?
Permanent
Is toludine temporary or permanent?
Permanent
Is iodine-KI temporary or permanent?
Temporary
What is eosin used for and what is its final colour?
Cellulose, red
What is toludine used for and what is its final colour?
Lignin and cellulose, red and purple
What is iodine-KI used for and what is its final colour?
Starch, blue-black
Name the two Romanowsky stains
Leishman’s and Wright’s
Leishman’s stain instructions
- Mix blood with methanol
- Flood slide
- Dilute with water
- Leave for 5 mins
- Wash slide until it appears pale pink
Wright’s stain is used for
Performing differential white blood cell counts, which are ordered when infection is suspected.
Why is a blood sample spread onto a slide by a machine?
Thin enough that individual cells can be seen and thick enough for it to be representative.
Give the instructions to prepare a blood smear by hand.
- Place drop of blood on dry, sterile microscope slide.
- Use another microscope slide at 30 degrees to pull the blood along.
- Label the slide with patient information
- Allow slide to dry so cells can stick to the slide
Use a fixative to preserve cells
