Differential staining and blood smears

Question 1

Name the stages of preparing a temporary slide

Answer 1

Fixation, staining, mounting

Question 2

Name the stages of preparing a permanent slide

Answer 2

Fixation, dehydration, clearing, embedding, sectioning, staining, mounting

Question 3

What is the advantage of preparing temporary slides?

Answer 3

Rapid and simple

Question 4

Describe fixation (temporary)

Answer 4

Add 70% alcohol

Question 5

Why is a specimen covered using a thin glass coverslip?

Answer 5

Exclude dust and air and protect the high power objective lens on the microscope

Question 6

Why might a specimen be mounted in glycerine after staining?

Answer 6

To stop the specimen from drying out so it can be observed for a longer period of time.

Question 7

Define differential staining

Answer 7

A staining process which uses more than one chemical stain.

Question 8

Give 3 advantages of using a preserved form of a specimen.

Answer 8

Enables specimen to be cut into sections, can be treated with a variety of stains, reveals different structures within the tissues and cells.

Question 9

Longitudinal section (area)

Answer 9

Vertical cut (length x width)

Question 10

Transverse section (area)

Answer 10

Horizontal cut (pi r2)

Question 11

Oblique section (area)

Answer 11

Diagonal cut (pi r1 r2)

Question 12

Is eosin temporary or permanent?

Answer 12

Permanent

Question 13

Is toludine temporary or permanent?

Answer 13

Permanent

Question 14

Is iodine-KI temporary or permanent?

Answer 14

Temporary

Question 15

What is eosin used for and what is its final colour?

Answer 15

Cellulose, red

Question 16

What is toludine used for and what is its final colour?

Answer 16

Lignin and cellulose, red and purple

Question 17

What is iodine-KI used for and what is its final colour?

Answer 17

Starch, blue-black

Question 18

Name the two Romanowsky stains

Answer 18

Leishman’s and Wright’s

Question 19

Leishman’s stain instructions

Answer 19

1. Mix blood with methanol
2. Flood slide
3. Dilute with water
4. Leave for 5 mins
5. Wash slide until it appears pale pink

Question 20

Wright’s stain is used for

Answer 20

Performing differential white blood cell counts, which are ordered when infection is suspected.

Question 21

Why is a blood sample spread onto a slide by a machine?

Answer 21

Thin enough that individual cells can be seen and thick enough for it to be representative.

Question 22

Give the instructions to prepare a blood smear by hand.

Answer 22

1. Place drop of blood on dry, sterile microscope slide.
2. Use another microscope slide at 30 degrees to pull the blood along.
3. Label the slide with patient information
4. Allow slide to dry so cells can stick to the slide
   Use a fixative to preserve cells