This is a great hands-on science lab where students will examine various specimens to observe different types of cells. The first sample has the students examine the letter “e” from a newspaper to help them become familiar with the various parts of a microscope.
Next, the students will peel a layer of skin from an onion to examine the skins cells underneath the microscope. The cell wall, cytoplasm, nucleus, and nucleolus should be easily visible.
After the onion, students will examine a leaf from the elodea plant. These plants are ideal for examination due to their thinness. Students should be able to see the cell wall, cytoplasm, and chloroplasts. If lucky, perhaps you can even find “cytoplasmic streaming” where you will witness chloroplasts floating around and drifting inside the plant cells.
Near the end, students will examine prepared slides of cork and blood. The examination of cork is more for historical reasons as cork was the first sample examined by Robert Hooke in 1665. Many states have laws against examining fresh blood due to the risk of blood-borne pathogens, which makes prepared slides of blood ideal.
Throughout the lab, there are probing questions to direct the students in their observation.
I usually spend two consecutive days performing this lab as many young students are very slow and cautious with using microscopes for the first time. The following materials are needed for this lab activity:
Onion (obtained from any grocery store)
Elodea plant (I always get my elodea from an aquarium store. Sometimes Petco and PetSmart will have elodea, but I have always found elodea at designated aquarium stores).
Prepared slide of cork (you can find these from any science supply store such as Wards or Carolina)
Prepared slide of blood (you can find these from any science supply store such as Wards or Carolina)
There are 4 files included in this download:
1) Student worksheet (Word format)
2) Student worksheet (PDF format)
3) Answer key (Word format)
4) Answer key (PDF format)