The hydra is a freshwater aquatic invertebrate, a relative of the jellyfish and coral as part of the phylum cnidaria. Its anatomy is simple: a hollow, tubular body and a set of tentacles.

At the base of the tentacles lies the opening to the gastrovascular cavity. The inside of this cavity is lined with a layer of tissue called the endoderm. The outermost layer of tissue is the ectoderm, and in between is a gelatinous substance called mesoglea.

Hydra are capable of many remarkable abilities, including asexual reproduction. This process is called “budding”, in which a bud grows from a hydra’s body and eventually breaks off and grows into an identical clone.

This experiment was designed to observe this activity and compare the results between to species of Hydra.

The hypothesis: the species hydra viridis (green hydra) will reproduce more rapidly than hydra oligactis (brown hydra).

Green hydra get their name from the green algae (called zoochlorellae) that live within the hydra's endodermal cells. The algae live off of the prey that the carnivorous hydra takes into its gastrovascular cavity, and as the algae undergo photosynthesis, they create sugars that the hydra uses for energy. Reproduction requires...