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Low budget digital microscopy for schools and informal learning environments

Anil Kumar Challa

When I began interacting with children (elementary to high school) in Hyderabad, I realized that it was not very easy to get them excited about biology. This was especially visible when one saw the excitement that chemistry experiments created. I could even bring some excitement into astronomy using the open-source Stellarium’ software. I wanted to hear the wow“s from kids when I talked about biology, as they do when they see the rings of Saturn through a telescope, or even the Sun spots through eclipse shades. I knew that peering into the microscopic world of life would definitely get children excited. Although, one particularly widespread challenge with using the commonly available microscopes (simple, as well as compound) is that specimens are not always obvious through the lens, for the uninitiated. Anyone who has used a microscope realizes that it takes a little of practice to begin seeing through the optics. And, it is not unusual for the observer to imagine details that don’t actually exist in the specimen. Digital microscopy overcomes these hurdles in optical microscopy by allowing the visualization of images on a monitor or computer screen. This is especially helpful in learning environments where students can be guided by using the images on the screen.

I learnt of small and economical digital microscopes that would allow me to take them to schools and informal learning environments. Two different makes of digital microscopes came to my notice and I liked the features of Motic DS-300. The specific feature that I liked in DS-300 was that it could be used as a conventional microscope with an eyepiece, and also as a digital microscope by swapping the eyepiece with a camera. The digital camera looked like a simple webcam and so I was concerned about the resolution. Nevertheless, since it was a reasonably affordable price for an interesting experiment in education, I took a chance.

My first experience using the Motic DS-300 microscope in a teaching & learning set-up was with a group of middle schoolers. I used the fixed slides that came along with the kit. It was easy to show them what I wanted them to see on the slides, using the MoticPlay software and the digital display on a computer screen. While the kids had a great time watching the slides directly using the eyepiece and on the screen (using the digital camera) I wasn’t satisfied since the material could have been a lot more interesting. Fortuitously, I happened to visit Dr.Surendra Ghaskadbi’s laboratory at the Agarkar Research Institute in Pune who kindly gave me some hydra. The hydra survived the flight trip back to Hyderabad and I was able to take them to the middle schooler children a week later. I first made all of them see the hydra at different magnifications using the eyepiece. The kids who could identify the hydra were very excited to see the obvious movement of the tentacles. The excitement of the entire group went beyond my expectations when I projected the digital views onto a large screen. The joy of seeing living specimens was immediately visible.

Unfortunately, I could not keep the hydra alive for long and had to fall back on the fixed slides that came along with the microscope. When I had to visit a seventh grade class in Shamshabad area (near the new airport in Hyderabad), I began to think about what live material I could use. I tried a few samples of stagnant water with little success of finding anything interesting. As the day of the visit came close, I remembered the experiments that we had to do in my high school botany laboratory — to understand the microscopic structure of plant roots and shoots. When I visited the school, I went into their play ground and plucked a couple of tender shoots. I made quick cross sections of the stem with a razor blade and placed them as specimens. I was impressed with the quality of images that showed up on the screen. The only problem was that I could not excite the students. I then realized that neither the shoot sections, nor anything inside them were animated.

Sometime later, I was able to access live paramecia cultures, newly hatched artemia (brine shrimp), and a tank filled with amazing creatures including a few species of rotifers. I am yet to show these beautiful creatures to school children, but quite a few undergraduate students and even graduate students have watched them under the microscope with amazement. The clarity with which one can observe the movements of paramecia, particularly the slipper shaped body of the protozoan at higher magnifications is remarkable. The rotifers present another spectacular view of the microscopic world. The movement of wheels’ or rotors’ on the heads of rotifers that generate currents to suck food material amazes everyone. The peculiar dichotomy of foraging behaviours is very evident when one scans through the tank water samples — in one instance they are motile in search of food, and in another instance they are sessile drawing food using their wheels’.

Not surprisingly, the developing zebrafish embryo can also be viewed very well with this microscope. Unlike the fast paced movements the single celled paramecia, and the wheel’ movements of the rotifers, watching the first day of zebrafish development requires patience and interest in understanding the fascinating mechanics of vertebrate embryogenesis. The second day of development can be quite exciting to everyone — the undifferentiated mass of cells during the first several hours of development transforms into distinct tissues and organs (e.g. somites and the eyes) by the end of 12 – 14 hours. The spontaneous body movements that become obvious from 18 hours after fertilization and the beating heart around 26 hours bring out the wow”s from children and adults alike.

With the Motic microscope in hand and access to a few live specimens I was able to go to a diverse range of learning environments to talk about the diversity in the living world, complexity present in simple’ and not so simple organisms, and the process of embryogenesis. This has been very easy since the microscope is very light weight and quite small in size, in addition to its affordability. Of course, I need my laptop to make a completely mobile and portable microscopy lab.

The mobile microscopy lab can be a valuable tool to get young minds excited about biology, and science in general. Biologists and teachers can team up to create simple lesson plans for these mobile labs, and extract the most from all the efforts. I strongly feel that these efforts, when expanded even modestly, contribute immensely to the enrichment of learning environments. Most importantly, there is great pleasure in sharing the excitement of science with young people. This is my testimony.

References and Links:
1. David Walker, A personal review of the Motic DigiScope 300 LED field microscope with digital camera. http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-…
2. User photos: http://​sites​.google​.com/​s​i​t​e​/​h​y​d​b​i​o​r​t​/​motic