Techniques in Histology

What is the purpose of embedding tissue samples in paraffin wax during histological processing?

• To fix the tissue

• To cut thinner sections

• To preserve the tissue structure

• To stain the tissue

What is the primary function of fixation in histology?

• To stain the tissue

• To preserve tissue structure

• To embed the tissue in wax

• To wash the tissue

What role does a microtome play in the preparation of histological slides?

• To stain tissue sections

• To fix tissue sections

• To cut tissue sections into thin slices

• To preserve tissue sections

What is the significance of clearing tissue samples during histological preparation?

• To enhance the staining process

• To remove excess water from the tissue

• To make the tissue transparent for embedding

• To fix the tissue structure

Describe the steps involved in Gram staining.

• Crystal violet, iodine, decolorizer, and safranin

• Safranin, iodine, decolorizer, and crystal violet

• Hematoxylin, eosin, decolorizer, and crystal violet

• PAS, iodine, decolorizer, and safranin

What is the significance of the iodine step in the Gram staining process?

• To act as a counterstain

• To enhance the crystal violet stain

• To wash away the stain

• To fix the safranin stain

Why do Gram-positive bacteria retain the crystal violet stain while Gram-negative bacteria do not?

• Gram-positive bacteria have thicker cell walls

• Gram-positive bacteria have thinner cell walls

• Gram-negative bacteria lack cell walls

• Gram-negative bacteria retain the crystal violet

How can you differentiate between Gram-positive and Gram-negative bacteria based on their color after staining?

• Gram-positive bacteria appear red; Gram-negative bacteria appear purple

• Gram-positive bacteria appear purple; Gram-negative bacteria appear red

• Gram-positive bacteria appear blue; Gram-negative bacteria appear green

• Gram-positive bacteria appear green; Gram-negative bacteria appear yellow

What is the most common reason a Gram-positive bacterium appears as Gram-negative after staining?

• The bacterium lacks a cell wall

• Over-decolorization during the Gram staining process

• The use of incorrect staining reagents

• The bacterium's cell wall has become thinner over time

What is the purpose of using xylene in histological processing?

• To fix the tissue

• To dehydrate the tissue

• To clear the tissue and remove embedding medium

• To stain the tissue