This is the picture of a sample of water from Baxter Pond. When looking at the water droplet without any tools, it appears that there is nothing in the water. However, while using the foldscope, I was able to see small objects or round organisms floating in the sample. Several of these round objects are shown in this image.

The sample of water from Baxter Pond was collected by the TA prior to our recitation session (Monday 7-8pm), and we were each able to put a drop of this sample onto a microscope slide. After securing it with a cover slip and tape, we used our foldscopes to magnify the contents of the slide. I ran into some issues with focusing the image, since my camera would shake near the magnets, and its quality is not very good in the first place. I found that holding it up against a bright light and taking a picture from an angle would improve the quality of the picture.

It took a long time to pan to an interesting spot on the slide and take a relatively clear picture. I did not have much time during recitation to learn more about whatever was photographed, so I have some questions and potential approaches to answering them.

1. What type of organism is it? –> To solve this problem, I would try ways to focus the camera more, allowing me to get a clearer picture of the round objects I found in the water, which are potentially some sort of bacteria or microorganism. With a clearer image, I would be able to identify features of interest, such as the contents of the body and whether it has flagella to help it move around, etc. I would also look into the types of microorganisms that are commonly found in water like the water in Baxter Pond and compare their characteristics to help me determine what it is.
2. How many organisms are in the scope of the image? –> I could find out what the average size of the organisms are, and use the magnification of my foldscope to give an approximate size of the area covered by my image. Then, I could do a simple calculation to find about how many organisms are present in that picture.

Overall, it was an interesting recitation session and a good way to practice using the foldscopes. It was a bit more difficult because we used a water sample instead of a dry sample; it was sometimes hard to tell if something was actually important or if it was a bubble/tape/dust. Hopefully this image is of something of interest.

#caltechbi1