AP Biology: Invertebrate Lab Questions

Phylum Porifera:
1. Sketch a Grantia cross section, and label: spongocoel, incurrent and radial canals, choanocytes epidermis, and gastrodermis.
2. There are 3 classes in this phylum. Upon what characteristic are these grouping based?

Phylum Cnidaria:
3. In what ways are hydra unique?
4. You are given a cnidarian. It spends its entire life as a free swimming medusa. To which class does it most likely belong?

Phylum Platyhelminthes:
5. Sketch a planarian, and label: head, eyespots, auricles, pharynx, and gastrovascular cavity.
6. Compare the location of the pharynx in a planarian to its location in a liver fluke.
7. You are given a flatworm with a scolex and proglottids, which reproduces by shedding its proglottids with its hosts feces. To which class of Platyhelminthes does it belong? Describe digestion in this organism.

Phylum Nematoda:
8. Describe the 2 'advancements' of nematodes over flatworms.

Phylum Rotifera:
9. Describe 3 similarities between rotiferans and nematodes.

Phylum Annelida:
10. Sketch an earthworm, and label: Mouth, pharynx, heart, seminal vesicles, esophagus, crop, gizzard, and dorsal blood vessel.
11. What are 3 external features you could use in determining to which class a given annelid belongs?
12. What are the functions of the typhlosole, seminal vesicles, and clitellum?

Other worm questions:
13. Distinguish between a pseudocoelom and a coelom and give an example of a worm that possesses each.
14. Explain the relationship between the tremendous number of eggs produced by flukes, tapeworms, and parasitic roundworms and the complexity of their life cycles.
15. The nematodes and rotifers are pseudocoelomates, even though they have a body cavity. Why is this cavity not considered to be a "true coelom?"

Phylum Arthropoda:
16. Explain the functions of a cheliped and a gastric mill in a crayfish. The gastric mill is similar in function to what structure in an earthworm?

Phylum Mollusca:
17. You are given a mollusk with one shell, that is spirally shaped. To what class does it probably belong?
18. When looking at a dissected clam, how can you tell the anterior from the posterior side?

Phylum Echinodermata:
19. You are given an echinoderm with tentacles and tube feet, but no arms or spines. To which class does it belong?