Question

3. What are the tentacles for? 4. What structure gives more firmness to the body? 5. Compare your specimen to the medusa stage you drew above. Observe the examples of anemones provided 1. What class do anemones belong to? 2. Which is the most dominate stage: polyp stage, medusa stage? 3. Are the tentacles on the oral side or aboral side? 4. How do anthozoans differ from hydrozoans? 5. How does this difference allow anemones to digest larger prey? 6. Compare your specimen to the polyp stage you drew above. Observe the examples of the skeletal structure of corals provided, and answer the following questions. You may need your textbook for help. 1. What class do corals belong to? 2. Which is the most dominate stage: polyp stage, medusa stage? 3. Corals secrete the calcium carbonate "skeleton" on the oral side or aboral side? 4. Instead of capturing prey (which some corals do), how do tropical corals obtain nutrition? 5. Observe images of corals feeding on the internet. Your instructor will show one in class, but you can do a video search for "live corals feeding" Page 4 of4

Answer 1

Answer

sea anemone

1) Sea anemone belongs to class Anthozoa of phylum cnidiaria

2) polyp stage is dominant

3) tentacles are at oral side

4)Characteristics of class Hydrozoa

-dominant polyp form

-cnidocytes present in epidermis only

-very small

-medusa, if present have velum, no gastric pouches, no oral arms

charactersrics of Class Anthozoa

-flowers of the oceans

-polyp form only

-gastrodermas divided by septa or mesenteries that bear nematocysts

-tentacles are solid

-may be hexamerous or octamerous

Anthozoan polyp: septate gut, stomodeum with siphonoglyphs, gastrodermal gonads, cellular mesoglea. Hydrozoan polyp is simple and lack other features.