Cheek Epithelial Cells: How to Prepare a Wet Mount Microscope Slide

Summary

This video demonstrates how to prepare a wet mount slide of epithelial cheek cells. The presenter explains the process, starting with gathering materials and wearing eye protection. Instead of water, a 9% sodium chloride solution is used to prevent cell bursting. A toothpick is used to collect the sample, which is then stained with methylene blue for visibility under a microscope. The cover slip is applied carefully to avoid air bubbles. The video shows cheek cells under 100x, 400x, and 1000x magnification, revealing their structure and the presence of oral bacteria.

Takeaways

• 🔬 The video demonstrates how to prepare a wet mount slide of epithelial cells from the inside of the cheek.
• 👓 Eye protection is essential before starting the experiment.
• 💧 Instead of water, 0.9% sodium chloride solution is used as it is isotonic to the cell fluid, preventing the cells from bursting due to osmotic pressure.
• 🦷 A toothpick is used to collect the cheek epithelial cell sample by gently running it inside the cheek.
• 🧪 The collected sample is mixed with the sodium chloride solution on the slide.
• ⚠️ The used toothpick is a biohazard and must be disposed of properly.
• 🟦 Methylene blue is used to stain the cheek cells, as they are transparent and hard to see under the microscope without staining.
• 🖼️ A cover slip is carefully placed at a right angle to the slide to prevent air bubbles and keep the slide neat.
• 🔍 At 100x magnification, cheek cells appear like 'little fried eggs,' with the blue dot representing the nucleus.
• 🔬 At 1000x magnification under oil immersion, bacteria from the mouth can also be seen on and around the cheek cells.

Q & A

What type of cells are being examined in this video?

The video examines eukaryotic animal cells, specifically epithelial cells from the inside of the cheek.

Why is sodium chloride solution used instead of water for the wet mount?

Sodium chloride solution is isotonic compared to the fluid inside the cells, preventing the cells from bursting due to osmotic pressure. Using water could cause the cells to burst.

How is the specimen collected for this slide preparation?

The specimen is collected by gently running a toothpick along the inside of the cheek, then swirling the end of the toothpick in a drop of sodium chloride solution on the microscope slide.

What stain is used in this process, and why is it needed?

Methylene blue is used as a stain because epithelial cells are very transparent. The stain makes the cells visible under the microscope.

What is the proper way to apply the cover slip over the specimen?

The cover slip should be held at a right angle to the slide and then dropped to avoid the formation of air bubbles.

What should be done if excess liquid seeps out from under the cover slip?

A paper towel can be used to blot up the excess liquid, but it must be treated as biohazardous waste and disposed of properly.

What do cheek cells look like at 100x magnification?

At 100x magnification, cheek cells resemble little fried eggs, with the blue dot inside each cell being the nucleus.

How do the cheek cells change in appearance at higher magnifications?

At 400x magnification, the cells appear much larger and more detailed. At 1,000x magnification, using oil immersion, you can see bacteria on and around the cheek cells.

What are the small dots seen in and around the cheek cells at high magnification?

The small dots are oral bacteria that come from the mouth and are visible on and around the cheek cells at 1,000x magnification.

What precautions must be taken with biohazardous materials during this process?

The used toothpick and any materials that come in contact with the cells, like the paper towel, must be treated as biohazardous and disposed of properly.