Final answer:
To prepare and observe a cheek cell specimen using a light microscope, collect a sample from the inside of your cheek using a sterile swab, create a smear on a slide, allow it to dry, then heat fix. Stain the specimen for enhanced visibility and begin observation with the low power objective before switching to high power to focus on individual cells.
Step-by-step explanation:
Preparing a Human Cheek Cell Specimen for Light Microscopy
To observe cheek cells under a light microscope, first obtain a prepared slide labeled “mouth smear”. A mouth smear slide will show squamous epithelial cells, which come from the outermost layer of the oral mucosa, with visible nuclei under both low and high power objectives. Next, collect a sample of your oral mucosa by using a sterile swab and gently rubbing the inside of your cheek. Smear the collected sample onto a clean glass slide to make a smear. After allowing the smear to air-dry, heat fix the specimen by quickly passing the slide through a Bunsen burner flame. This step will affix the cells to the slide.
For a more detailed examination and to enhance visibility, you may need to perform staining techniques, such as the Gram stain, to differentiate cell structures and bacteria present on the cheek cells. Staining provides contrast and can help in identifying cell morphology and bacterial presence. Once the slide is prepared and stained, place it under the microscope. Starting with the low power objective, locate a squamous epithelial cell. Switch to a higher power objective to focus on a single cheek cell and observe finer details such as the cell membrane and nucleus. In addition to this, look for the presence of bacterial cells on or near the cheek cell and note the scale of these bacterial cells relative to the size of the cheek cell. Sketch the cheek cell including the bacteria, labeling the cell membrane, cytoplasm, and nucleus. Following proper microscopic techniques ensures that your observations are accurate and that you preserve the integrity of the specimen.