What’s in the Water?
Did you know that 71% of the Earth’s surface is water? We see it everywhere – lakes, rivers, beaches, and countless more places. However, the water that we see is not just pure H2O as we would could believe. In fact, in addition to dirt and other natural impurities, microorganisms live in our water supplies. These living microorganisms can be in the form of bacteria, viruses, and protozeans and that may either be harmful or safe for human consumption but rely on our water supplies to survive. While it is difficult to identify these microorganisms with our naked eye, using a biological microscope can bring our water to life. What we had previously thought was just cloudy pond water is in fact teeming with microorganisms that look like little critters that move around in the water. Today, we will be looking for some in a variety of water sources and making our own sample slides.
According to Microbus 2015, you may be able to find microorganisms such as the Phylum Ciliophora, Phylum Mastigophora, Phylum Sarcodina and more. Click here for information about these microorganisms including what they look like.
Now it’s your turn. After completing this task, you will have first-hand knowledge of what lies inside our water. Please keep in mind that our drinking water undergoes a great deal of filtration in order to remove harmful impurities. Water found in nature, such as lakes, beaches and more tend not to be filtered so please do not consume any water you have gathered in the following task.
Water Sample Experiment
Materials
- Eyedropper
- A variety of water samples from different sources – rain water, puddle, pond water, local creek, etc.
- Blank slides
- Cover slips
- Microscope
Instructions
- Get some water samples from a variety of sources – a local creek, a tap, a pond, rain water, bottled water, a puddle or more.
- Get some blank slides and cover slips.
- Using a marker or pen, label each of the slides with CREEK, TAP, POND, POOL, corresponding to the sources of the water samples you have collected.
- Using an eyedropper, take 1-2 drops of each water sample and place it on the corresponding slides. Remember to clean your eyedropper thoroughly between use.
- Carefully and slowly place a cover slip on top of each water droplet to prevent contamination and to hold the water samples in place. Doing it slowly is important so as to prevent the water from splattering everywhere.
- Observe your new slides under a microscope. For greatest effect, you may need to use your highest magnification (400x+ recommended)
- Draw your slides out and remember to label them. What can you see?
Water Samples Worksheet
| Tap | |
| Creek | |
| Pond | |
| Pool | |
| Rain water | |
| Puddle |
If you have any questions about the experiment or anything you learned today, don’t hesitate to contact OpticsCentral on support@opticscentral.com.au or leave a message on our Facebook page.
Don’t forget to ‘Like’ us for daily updates on the experiments we have in store for you this National ScienceWeek.
Catch up on the previous days:
