Microscopes!

Lately we have been getting a lot of use out of one of the most important tools in biology- the microscope!  We talked about why microscopes are used, identified the names and functions of the important parts of the compound light microscope, discussed different types of microscopes and their advantages/disadvantages, and got LOTS of practice using the microscopes!  Students spent a few days working their way through eight different introductory microscope lab stations in which they practiced various microscope skills, including positioning, making a wet mount slide, and staining a specimen.

At this station, students tried various actions with the microscope to see what would happen to the images they were viewing.

At this station, students viewed a small section of potato unstained, and then stained the specimen and viewed it.

After this, students used their newly refreshed microscope skills to complete a lab that had three parts.  Part 1 was an opportunity to look at animal cells- their own!  Students scraped the inside of their cheek (gently) with a toothpick to loosen some cheek cells onto the toothpick.  They then scraped the toothpick onto a microscope slide and stained the cells with methylene blue stain.  Students put the slide onto the microscope and viewed their own cells!

 A sample of student cheek cells viewed at 100x magnification under the microscope (stained).

Students use microscopes to view their own cheek cells!

During the second part of the lab, students made slides of plant cells to view.  Students were given a section of thin onion skin, which they used to make a wet mount slide and stained with iodine.  

Students view and draw onion skin cells.

A sample of onion skin cells viewed at 100x magnification (stained).

For the third part of this lab, I went out to the wetland on our campus and collected some pond water.  Students took samples of the pond water and viewed them under the microscope with the hope of finding some critters moving around in the water.  Some were more successful than others!  Many of the little organisms that live in the water move so quickly that it is hard to get them in the field of view long enough to see them, but we did our best.  We did see a few really cool and creepy looking organisms!

What are we looking at?!

One of our pond water specimens!