Chapter 8
1. Invertebrates-animals that lack a vertebral column.
2. Vertebrates-animals that have a vertebral column.
3. Sessile-animals permanently attached to a solid surface.
4. Ostia-holes in the body of sponges through which water enters.
5. Spongocoel-cavity in the body of a sponge.
6. Osculum-an opening through which a sponge expels water.
7. Tissues-groups of specialized cells that performed a specific function.
8. Collar Cells (Choanocytes)-flagellated cells in a sponge’s body that circulates water and trap food.
9. Pinacocytes-cells that makeup the outer covering of a sponge and line internal chamber not lined by choanocytes.
10. Archaeocytes-cells that form any of the cell types in a sponge body.
11. Spicules-structures that support a sponge’s body.
12. Asconoid-type of sponge body that lacks invaginations in the body wall.
13. Syconoid-type of sponge body with a single spongocoel containing many invaginations.
14. Leuconoid-type of sponge body with multiple spongocoels and chambers leading to them.
15. Suspension Feeder-an organism that feeds on food suspended in the water.
16. Filter Feeder-organism that filters its food from the water.
17. Budding-type of asexual reproduction in which a group of cells on the surface of the parent develop into a new individual.
18. Hermaphrodites-animals that can produce both male and female gametes.
19. Photoperiod-relative amount of light and darkness in a 24-hour period.
20. Amphiblastula-the planktonic larval stage of a sponge.
21. Cnidarian-animal that belongs to the phylum Cnidaria.
22. Cnidocyte-stinging cell found in all cnidarians.
23. Radial Symmetry-organization of body parts around a central axis.
24. Polyp-benthic form of cnidarian characterized by a cylindrical body with an opening at one end, usually surrounded by tentacles.
25. Medusa-free floating form of a cnidarian that resembles an umbrella.
26. Epidermis-outer layer of cells.
27. Gastrovascular Cavity-large cavity found within the body of some animals.
28. Gastrodermis-layer of cells that lines the gastrovascular cavity.
29. Mesoglea-gelatinous material found between the epidermis and gastrodermis of cnidarians.
30. Cnida-stinging organelle of a cnidocyte.
31. Nematocyst-spearing type of Cnida.
32. Cnidocil-short bristle-like structure that acts as a trigger for a cnidocyte.
33. Hydrozoans/ Hydroid -mostly colonial cnidarians that belong to the class of hydrozoa.
34. Feeding Polyp (Gastrozooid)-polyp in a hydrozoan colony that captures food for the colony.
35. Reproductive Polyp (Gonangium)-polyp in a hydrozoan colony that asexually reproduces hydrozoan medusa.
36. Scyphozoans-cnidarians known ass jellyfish belonging to the class Scyphozoa.
37. Photoreceptors-light sensing organs.
38. Cubozoans-cnidarians known as box jellyfish belonging to the class of Cubozoa.
39. Anthozoans-benthic cnidarians belonging to the class of Anthozoa.
40. Sedentary-animals can move but spend the majority of time staying in one place.
41. Scleractinian Corals-corals with hard skeletons of calcium carbonate.
42. Octocorals-soft corals whose polyps have 8 tentacles.
43. Gorgonians-soft corals that belong to the order of Gorgonacea.
44. Planula Larva-planktonic larval stage of a cnidarian.
45. Pedal Laceration-asexual reproduction that occurs in sea anemones in which a portion of the animal’s base is broken off and forms a new individual.
46. Pedal Disk-base of the sea anemone.
47. Fission-asexual reproduction that occurs I sea anemones in which the anemone splits into two and each half develops into a new