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Euglena Experiment Biology 101 Euglena are one-celled organisms in the Protista kingdom. They are usually photosynthetic autotrophs but they have the ability to live as heterotrophs b y ingesting food. They do this when photosynthesis is not possible. Euglena are highly motile and reproduce rapidly. In this experiment I intend to collect enough data to back up my hypothesis. My hypothesis is that the Euglena are attracted to darkness.

The material that I used were a microscope, a clean glass slide, a cover slip, a small dish filled with water, a piece of construction paper, a colony of Euglena and a dropper.

First I prepared my microscope by placing the small clear glass dish full of water over the light source in the base of the microscope to absorb heat. Next I placed two drops of Euglena in the center of the clean glass slide. I then took a cover slip and placed one edge on the side of the Euglena and lowered it down slowly like I was closing a book.

I did this to prevent trapping air bubbles. I then cut a small piece of construction paper to put around the slide so that half of the square containing Euglena was in the dark and the other half was in the light. Then I positioned the slide so that it was in my field of view. I used the 4x scanning objective lens to locate the Euglena and then switched to the 10x objective and focused in on the specimens. I then timed a minute on my watch and counted how many Euglena were in my field of view. I repeated these steps three times. I then started a control group of Euglena by making the slide the same way but without placing the construction paper on top. I timed a minute and counter how many Euglena were in my field of view. I repeated this step three times.