When preparing a wet mount specimen for viewing under a microscope, which of the following steps is essential to prevent air bubbles from forming under the coverslip?

• A. Use a dry slide without adding any liquid
• B. Place the coverslip directly and quickly onto the specimen
• C. Blot the specimen with paper before adding the coverslip
• D. Lower the coverslip slowly at an angle onto the drop of specimen

Answer: (D)

Verified step by step guidance

1. Understand the purpose of preparing a wet mount: it allows observation of living microorganisms or cells in a liquid environment under the microscope.
2. Recognize that air bubbles under the coverslip can obstruct the view and interfere with proper observation of the specimen.
3. Recall that to avoid air bubbles, the coverslip should not be placed abruptly or directly flat onto the slide; instead, it should be lowered slowly.
4. Lower the coverslip at an angle onto the drop of specimen, allowing the liquid to spread evenly and air to escape gradually, preventing bubble formation.
5. Avoid using a dry slide without liquid or blotting the specimen before adding the coverslip, as these do not address the issue of air bubbles effectively.