1. The reproductive structures of an earthworm are located

A. under the clitellum.
B. mid-way along the length of the worm.
C. closer to the anterior end of the worm.
D. closer to the posterior end of the worm.

2. The setae of the earthworm function BEST for

A. traction.
B. feeling.
C. excretion.
D. subdividing the coelom.

3. In order to elongate, an earthworm would have to

A. contract its circular muscles, while relaxing its longitudinal muscles.
B. relax its circular muscles, while contracting its longitudinal muscles.
C. contract both its circular and longitudinal muscles.
D. relax both its circular and longitudinal muscles.

4. Of the following, which is the BEST description of detritus?

A. Fungus.
B. Fertilizer.
C. Soil debris.
D. Undigested wastes.

5. The aortic arches of an earthworm are located around the

A. pharynx.
B. intestine.
C. esophagus.
D. ventral nerve cord.

6. Which of the following pairs in mismatched?

A. Gastropod — mantle cavity.
B. Bivalvia — water vascular system.
C. Oligochaete — segments.
D. Hirudinea — suckers.

7. Which pair most correctly matches structures with their functions?

A. Crop — storage; gizzard — grinding.
B. Crop — grinding; gizzard — storage.
C. Crop — chemical digestion; gizzard — physical digestion.
D. Crop — physical digestion; gizzard — chemical digestion.

8. Earthworms are MOST correctly described as

A. free-living.
B. parasitic.
C. carnivores.
D. herbivores.

9. The annelid feature that “relates” best to mollusks is the

A. degree of specialization of the nervous system.
B. lack of development of an excretory system.
C. development of ciliated larvae.
D. extent to which their bodies are segmented.

10. The correct sequence of the parts of an earthworm’s digestive system is

A. pharynx, crop, gizzard, intestine, anus.
B. pharynx, gizzard, crop, intestine, anus.
C. esophagus, gizzard, crop, intestine, anus.
D. esophagus, crop, gizzard, stomach, intestine.

11. The lifestyle of a polychaete is best described as

A. predator.
B. prey.
C. producer.
D. parasite.

12. Which of the following systems is likely the MOST developed in a leech?

A. Excretory.
B. Reproductive.
C. Digestive.
D. Circulatory.

13. The chemical secreted by a leech is medically significant because it prevents

A. bacterial infection.
B. blood clotting.
C. tissue rejection.
D. skin deterioration.

14. Which of the following sets of features most accurately defines Phylum Mollusca?

A. Marine, soft-bodied, mantle.
B. Soft-bodied, mantle, closed circulatory system.
C. Foot, mantle, soft-bodied.
D. Marine or terrestrial, foot, open circulatory system.

15. Which of the following is LEAST likely a function of the siphon of a clam?

A. Feeding.
B. Excreting.
C. Circulating.
D. Reproducing.

16. A sinus of a clam is MOST correctly described as a chamber where

A. air collects for respiration.
B. blood collects to bathe tissues.
C. muscles for movement are located.
D. reproductive gametes are stored.

17. Which of the following are vestigial structures?

A. Gills of clams.
B. Mantles of slugs.
C. Eyes of octopi.
D. Radulas of snails.

18. Which organism is mismatched with a characteristic “lifestyle”?

A. Clam — filter feeder.
B. Squid — predator.
C. Slug — carnivore.
D. Snail — free-living.

19. Which part of the water vascular system of a sea star is connected directly to a tube foot?

A. Madreporite.
B. Lateral canal.
C. Ring canal.
D. Radial canal.

20. Which system of echinoderms is LEAST specialized?

A. Digestive system.
B. Locomotory.
C. Respiratory.
D. Reproductive.