Question

During staining, the smear is heat-fixed in order to_____ .

• A. kill the organism so that dyes will penetrate
• B. attach the organism firmly to the slide
• C. kill the organism and attach the organism firmly to the slide
• D. neither kill the organism nor attach the organism firmly to the slide

Hint:

Heat-fixing not only kills the organism but also secures it to the slide for efficient staining and analysis.

Answer 1

The Correct Option is C

Step 1: Purpose of Heat-Fixing
Heat fixation is an essential step in staining procedures. It is performed by gently heating the slide with the smear, which helps in killing the microorganisms. Additionally, it helps in attaching the microorganisms firmly to the slide, making it easier for the subsequent steps of staining to occur.

Step 2: Why This is Important
- Killing the organisms ensures that the microorganisms do not continue to grow during the staining process.
- Attaching the organism firmly to the slide prevents it from being washed away during subsequent staining and washing steps.

Step 3: Conclusion
Thus, the correct answer is (C) because heat-fixing achieves both purposes: killing the organism and securing it to the slide.