A drop of untreated water is a very small world. Hundreds of small microorganisms like protozoans, bacteria and algae live there. We have colected different samples of water; in the laboratory we have deposited drops of water onto a glass slide, we have covered it with a cover slip and observed with a microscopy. There are lots of different small organisms living there. Here you have some pictures taken in our laboratory. We have observed protozoans like Paramecium or Vorticella, algae, even small pluricelular animals as rotifers, also known as wheel animals. We have found some parasite eggs too!
What do you think about our experience? Try to draw one of these small organisms; I will publish the best drawings in our blog.