Question

During tissue processing, what is the correct sequence of steps?

• A. Clearing, Dehydration, Infiltration
• B. Dehydration, Infiltration, Clearing
• C. Infiltration, Dehydration, Clearing
• D. Dehydration, Clearing, Infiltration

Hint:

Tissue processing order = Remove water (Dehydration) → Replace with clearing agent (Clearing) → Impregnate with wax (Infiltration).

Answer 1

The Correct Option is D

Step 1: Recall tissue processing steps.
Tissue processing prepares biological tissues for microscopic examination. The goal is to preserve the tissue structure and allow infiltration of embedding medium (paraffin).
Step 2: Sequence of steps.
1. Dehydration: Removal of water from tissues using increasing concentrations of alcohol.
2. Clearing: Replacement of alcohol with a clearing agent (e.g., xylene) which makes tissue transparent.
3. Infiltration: Embedding medium (e.g., paraffin wax) penetrates the tissue.
Step 3: Exclude incorrect orders.
- (A) Clearing first is impossible since dehydration must precede it.
- (B) Infiltration before clearing is not correct.
- (C) Infiltration before dehydration is not possible.
- (D) Correct order = Dehydration → Clearing → Infiltration.
Step 4: Conclusion.
The correct sequence is Dehydration, Clearing, Infiltration.