Hydra Lab Materials: Slide of preserved budding hydra Living specimens of hudra Conclave slides Microscopes Daphnia or fish food Prelab Questions: 1. The Hydra belongs to the Kingdom _______________ and the Phylum ______________________ 2. What are cnidocytes? 3. Where do hydra live? 4. Name two other organisms that are closely related to the hydra.

Hydra Anatomy

Obtain a slide of a preserved hydra and view the slide under scanning and low power

1. Sketch the hydra. Label the basal disk, tentacles, nematocysts, bud, and gastrovascular cavity.

2. Count the number of tentacles on your hydra. How does the number of tentacles on your hydra compare to others in the class? Do they all have the same number of tentacles?

Hydra Behavior

Obtain a slide of a living hydra and view under scanning and low power. No coverslip will be added so that the hydra has room to move around. (Do NOT use the high power objective)

3. Observe your living hydra for a few minutes. How can you tell that the hydra is alive?

4. Gently touch the hydra's tentacles and basal disk with a toothpick. Be careful not to squish or damage your hydra. Describe how the hydra reacts to this stimulus.

5. Place food onto the slide (use living daphnia or fish food flakes). Describe how the hydra reacts to the food. It may take a little for the hydra to respond so be patient.