Virtual Microscopy Lab Exercise

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Virtual Microscopy Lab Exercise

  1. Copy and paste the below link into your computer internet browser:

https://www.ncbionetwork.org/iet/microscope/

  1. Click on the guide. What are the learning objectives of this virtual lab?

  2. Click on Main then Click on learn. Click on the ?s to identify the different microscopy parts. Then label the parts of the microscope below.

  1. Click on Main and then click on Explore. In the next set of activities you are going to use your virtual microscope to view several different specimen. Before you view your specimen, you should know how to calculate the total magnification you are viewing a sample with you use different objective lens on the microscope. Two lenses magnify samples when you are using a compound light microscope (ocular lens and the objective lens). The total magnification can be calculated using the following equation:

Ocular lens magnification ____ X objective lens magnification ___ = _____ total magnification

The ocular lens has a magnification of 10 and the objective lens magnification is always listed on the outside of the lens (4X, 10X, 40X or 100X). For example, if you are viewing a sample with the 40X objective, the total magnification of the viewed specimen would be 400X (10X times 40X). 

  1. Click on the Specimen box next to the virtual microscope. Click on the sample slides and then the letter e slide so that the slide is loaded onto the microscope. The 4X objective will automatically be put in place. Now focus the sample by moving the course knob and then the fine knob. Draw a picture of the letter e using the 4X objective. Be sure to include the total magnification of the sample. Now change to the 10X objective and draw this image (record the total magnification of the sample on the drawing). You may need to adjust the focus and light to get a sharp image.

  2. Now click remove slide (right corner of box). Click on the specimen box again and then click on the plant slide. Focus the sample and then click on the 10X objective. Refocus the sample and adjust the light. Draw the plant cells that you see in your field of view. Label the nucleus, cell wall, cell membrane cytoplasm and chloroplasts in one of the cells you draw. Be sure to record the total magnification or the image. Now change the 40X objective, adjust the microscope to achieve a focused image and draw what you see in the field of view. Label the same parts of the cell (nucleus, cytoplasm, cell membrane, cell wall and chloroplasts). Remove the slide.

  3. Click on the specimen box and then click on the animal slides. Select the spider slide. Focus the sample and then draw the image you see (record the total magnification). Remove the slide. 

  4. Click on the specimen box and then click on the bacteria slides. Then click on the acid fast stain bacterial slide. Focus the sample and then gradually move the objectives up to the 100x objective. You will need to add oil to this slide when using the 100X objective. You will need to adjust the focus and light when using this objective. Bacteria are prokaryotes which are much smaller than eukaryotic cells (e.g prokaryotic cells are 1-10 micrometers in length vs. eukaryotic cells are 10-100 micrometers in length). The cells that are stained on the slide are very small. You will notice that some of the cells are clumped together in larger masses while others are spread out and appear as tiny dots. Now, draw a picture of the stained bacteria. Be sure to include the total magnification of the sample. 

  5. What do you notice about the level of detail that can be seen when viewing the bacteria compared to the plant cells?

  6. Remove the bacteria slide and clean the oil off the objective with lens paper.

  7. Now remove the slide and click on main. Then click on test. Go through the different areas to see how well you remember the information. The practice test will help prepare you for the lab exam.

  8. When you are done testing the knowledge you acquired from the lab, put all collected information into a lab report (objective, materials and methods, results, conclusion) and turn the assignment into the appropriate assignment link on D2L. Hint: all diagrams, pictures and answers to questions should go in the result section.