Think about geothermal energy, plate tectonics, tides, mountain formation, and atmospheric conditions. Describe several ways the formation and presence of the moon changed life on Earth. Protozoans are unicellular organisms that have a true nucleus. They live in fresh water and salt water. Some live independently, whereas others live in colonies.
Most protozoans are heterotrophs, whereas others are autotrophs.
Have your students research the difference between autotrophs and heterotrophs and then list and draw protozoans that fall in each category. Students should be prepared to give a rationale for placing a particular protozoan in a category. Finally, have your students collect water samples to analyze under microscopes. Using reference books to help them identify the protozoans, students should draw and label as well as compare and contrast what they observe. False ideas, myths, and superstitions were deeply rooted in the thinking of people at the time.