Sponges and Cnidarians

1. What is an animal?

Animals are Heterotrophic, Eukaryotic, Multicellular, and Lack cell walls.

2. Roughly 3-5% of all animals have what?

Backbones

3. Aquatic animals that strain floating plants and animals from the water they take in are

called what?

Filter Feeders

4. What are the seven essential functions that all animals do in order to survive?

Feeding, Respiration, Circulation, Excretion, Response, Movement, Reproduction

5. What terms are associated with the body plan of sponges?

Sponge “skeletons” are supported by either spiny spicules (in harder sponges) or by a network of flexible protein fibers called spongin (softer sponges).

6. Sponges reproduce sexually by a process called what?

Spawning

7. Which essential function of animals would best describe why a sponge releases toxins

when predators are near?

Response because a sponge repsonds to stimuli when it feels threatened.

8. Why are flagella important to the essential functions within a sponge?

Flagella are used by the sponge to create water currents to bring new food closer, so the sponge can filter feed.

9. Sponges benefit some marine animals, how?

Some form mutualistic benefits with the sponge, while other use it as a home.

10. What symbiotic relationships do sponges form?

Sponges form mutualistic relationships with other organisms like bacteria, algae, and plant like protists. This contributes to the sponges color.

11. What do cnidocytes do?

Cnidocytes are specialized, stinging cells that eject poisonous fluid.

12. Which are the simplest animals to have body symmetry?

Cnidarians

13. Which two functions do nematocysts perform?

prey capture and defense

14. What are three characteristics of cnidarians?

They are soft-bodied, carnivorous animals, they have stinging tentacles arranged in circles around their mouths, they are the simplest animals to exhibit body symmetry and specialized tissues.

15. What are two basic body types of cnidarians?

Polyp and Medusa

16. The body symmetry of a cnidarian is what?

Radial

17. How do polyps differ from medusas?

Polyps mouth faces upwards and do not move, while medusas have their mouths on the

bottom and can move.

18. The specialized nerve cells of cnidarians make up what?

A nerve net made of cnidocytes

19. In jellyfishes, the medusa stage reproduces how?

Sexually

20. A cnidarian’s gastrovascular cavity is specialized for what?

Digestion

21. The Portuguese man-of-war is a member of what class of cnidarians?

A floating colony of polyps

22. Coral reefs occur in areas where there are what three factors?

Temperature, water depth, and light intensity.

23. Many cnidarians can live only in bright light because they depend on what?

Algae that needs the sun to photosynthesize.

24. What does coral reef “bleaching” mean?

Coral bleaching is when the environment disturbs the algae that coral has a mutualistic relationship with and causes the coral to lose its color and have a higher mortq.

25. What are three causes of coral reef “bleaching”?

Change in ocean temperature, runoff and pollution, overexposure to sunlight, extreme low tide