What is the primary purpose of using a biological stain when microscopically examining cellular components?

• A. To increase the contrast between different structures within the cell
• B. To sterilize the specimen before observation
• C. To prevent the specimen from drying out during examination
• D. To magnify the specimen beyond the capability of the microscope

Answer: (A)

Verified step by step guidance

1. Understand that biological stains are dyes or chemicals used in microscopy to enhance the visibility of cellular components by adding color to them.
2. Recognize that many cellular structures are transparent or have very little natural color, making it difficult to distinguish different parts under a microscope without staining.
3. Identify that the primary purpose of staining is to increase the contrast between different structures within the cell, allowing for clearer differentiation and better observation.
4. Note that staining does not sterilize the specimen, prevent drying, or magnify the specimen; these functions are unrelated to the role of stains.
5. Conclude that the correct purpose of using a biological stain is to increase contrast, which improves the ability to observe and study cellular components microscopically.