Reading 27-4: Mollusks

Issues in Biology: What Can Be Done About the Zebra Mussel (p700)

1. How did the zebra mussel get to the United States? __________________________
2. What problems do the zebra mussels cause for companies? _____________________________
3. What problems have they caused for native wildlife? ________________________________________
4. What beneficial use might the zebra mussels have? _________________________________________
5. How are chemists approaching the zebra mussel problem? _________________________________

27-4 Mollusks

6. The Latin word "molluscus" means: _______________________
7. Name three animals that are considered to be mollusks: ________________________________________________
8. What is the larval stage of the mollusk called: _________________________________________

9. Label:

A. _________________________

B. ________________________

C. ________________________

D. ________________________


10. What are the four parts of the mollusk body? __________________________________________________
11. Do all mollusks have a shell? ______________
13. In what part of the body do you find the mollusk's internal organs? _______________________________
14. What is the radula? ________________________________________________________
What animals have a radula? ____________________________

15. How do clams and oysters get their food?______________________________________________
16. Do land snails and slugs have gills? ____________ Where do they usually live? ____________________
17. What type of circulatory system do clams and snails have? ______________________
18. Nephridia remove what substance from the body? _________________________________
19. What type of mollusk can perform simple tasks and be trained? _____________________________

20. How does the octopus move? ______________________________________
21. (Fig 27-24) How does a snail defend itself? ________________________ An octopus? _____________
22. Name two animals in the Gastropod class: _______________________________
23. Gastropods are mollusks that move using a muscular _________________ located on the ______________ side.
24. What gastropod is brightly colored (and is poisonous!) _____________________________
25. What CLASS of mollusk has two shells that are held together by powerful muscles: _____________________
26. How do scallops move around? _______________________________________
27. Name four animals in the Class Cephalopoda: _____________________________________________
28. The foot of a cephalopod is divided into ____________________________________________
29. What is the only cephalopod that has an external shell? ______________________________________
30. What is the internal shell found on squid called? ________________________

Analyzing Data (p. 707)

31. What is aquaculture? _____________________________________________________________
32. When do Georgian clams grow? _________________________________
33. How many years does it take for the clams to reach a size where they can be removed from hatcheries and put into the creeks? __________________
34. At five years, how large are the clams? _______________________
35. How large are the clams at 10 years? __________________________
36. The most rapid growth of the clams occurs in: a. 1-5 years b. 4-6 years c. 5-10 years

Ecology of Mollusks

37. How do mollusks "clean up" their surroundings? _____________________________________________________
38. Bivalves near "black smokers" are dependent upon __________________________ to produce their food.
39. Bivalves can be used to monitor _______________________________________
40. Some mollusks never seem to develop what disease? ________________________

Labeling (Reference Fig 27-23)