1.  Why are both the Mollusks and the Arthropods considered to be Protostomes?
      2.  In what way is the coelom of Mollusks and Arthropods similar?
      3.  In what way is the nervous system of Mollusks and Arthropods different?
      4.  With the exception of one or two groups, what is a fundamental difference between most Mollusks and
            most Arthropods?
      5.  Give one or two examples of how Arthropods differ from Annelids.
      6.  What is a "giant neuron" and what function does it have in the Mollusks?
      7.  In what way does the control of "skeletal" muscle in Arthropods differ from that of Vertebrates?
      8.  What is the role of MIH ("moult inhibiting hormone") in Arthropods?
      9.  Why doesn't the mass of the calcareous shell of Cephalopods prevent the animal from sinking?
     10.  What are the consequences of torsion in Mollusks?
     11.  Name and distinguish between three major groups of Gastropods.
     12.  Discuss, briefly, the function of several portions of the eulamellibranch gill.
     13.  Contrast vision in a Mollusk with that of an Arthropod.
     14.  What is a biramous appendage?
     15.  Distinguish between Merostomatids and Trilobites.
 
Slightly longer answer questions:
 
1.  What are some morphological and/or physiological consequences of the possession of a cuticle (exoskeleton) by
 all arthropods?
2.  Describe the innervation of insect muscle.
3.  Discuss and contrast locomotion and mobility in the following three mollusks: a) Mercenaria - a clam; b) Helix - a
 snail; and, c) Loligo - a squid.
4.  Illustrate the movement of water thru a eulamellibranch bivalve.
5.  What evolutionary patterns are seen in Polychaetes that allow them to exploit a number of habitats and trophic
     levels?
 

Define the following terms:
 
 1.  pseudofeces -
 2.  suprabranchial chamber -
 3.  branchial heart -
 4.  radula -
 5.  adductor muscle -
 6.  crystalline style -
 7.  branchiostegite -
 8.  condyle -
 9.  sensilla -
10.  trilobite -
11.  uropod -
12.  antennal gland -
 

Supply the best word(s) that complete(s) the sense of the statement or question.  In some cases, the statement is
actually a definition, and you must supply the word that the statement defined.
 
1. ____________________________ - means the division of the body into similar parts, or segments, which are arranged in a linear series along the antero-posterior axis.

2. Contraction of the longitudinal muscles in a segment of an earthworm causes the body to become __________________________ .

3. _____________________________ - is a sheet of mesodermal tissue that is found in the sagittal plane of an annelid; it serves to support the blood vessels and gut.

4. The parapodium is basically biramous, consisting of an upper division, the  ______________________________ , and a ventral division, the _______________________________ .

5. The Errant Polychaetes are considered to be more _______________________ , since they retain most of the typical characteristics of these worms, including a well developed head.

6. The bloodworms (such as Glycera) are well known because they may immobilize their prey with ___________________________________________.

7. Amphitrite is a burrowing worm that still depends on surface detritus and organic matter as a source of nutrition; therefore, with regard to its trophic level, it is called a ____________________________________________________ .

8. Filter feeding has evolved in what group of polychaetes? ___________________________________________ .

9. The hemoglobin of polychaetes has the property of binding to oxygen until the partial pressure of oxygen
drops to well below 50 mm Hg; therefore, we consider this type of blood to function in _____________________________ .

10. _________________________________ - a type of kidney found in polychaetes that is tubular and open at both ends.

11. ________________________________ - is the larval form which is shared by many invertebrates of the Protostomous line.

12. The ventral, or segmental, ganglia of annelids contain ____________________________________ which are responsible for the rapid conduction of information throughout the animal.

13. ________________________________________ .

14. ______________________________________________ - refers to the movement of water ventro- dorsally in the mantle cavity, and the passage of blood dorso-ventrally in the gill filament.

15. Most molluscs, with the exception of bivalves, possess a __________________________ , which is used in the initial maceration of food.

16. The edge of the mantle of molluscs is responsible for the secretion of the ____________________________ and the ___________________________ .

17. A _____________________________ gastropod shell is one where the aperture is to the right of the columella when the shell is held with the apex up.

18. The phenomenon of "torsion" has resulted in the reduction of various internal organs and gills on the _________________ side of many Prosobranch gastropods.

19. The sea hares (Anaspidean), sea butterflies (pteropods), nudibranchs, etc. all belong to the S.C. _________________________________ in the Class Gastropoda.

20. Although the planktonic larvae of marine snails have shells, they are able to remain suspended in the water column because of the presence of a _______________________________________ .

21. The _____________________________________ is a group of molluscs, resembling limpets but with
distinct segmentation, that made a remarkable appearance as living organisms in 1952; they were last known from
the fossils record, and disappeared in the Devonian.

22. It has recently been shown that many species of extant bivalves can live to be quite old; the proof for this
lies in presence of  __________________________________________ in the shell.

23. Bivalves make extensive use of cilia, especially for feeding; the
______________________________________________ cilia function primarily in the sorting of particles, which are
then sent on to the palps and mouth.

24. The _______________________________________________ is a "pestle-like" structure that serves to
grind small particles in the stomach of bivalves, and at the same time releases
_________________________________ that also break down the particles.

25. The introduction of ____________________________ into the chamber of the Nautilus must be
accompanied by the absorption of ___________________________ since the chamber is sealed off from the
siphuncle.

26. The direct eye of many cephalopods probably forms an image; although strikingly similar to vertebrate
eyes, it differs in that the cone like retinal receptors are located
___________________________________________________________________ .

27. The ____________________________________ are points on the arthropod cuticle, similar to a ball and
socket joint and around which the segments rotate.

28. The ____________________________________ is the epithelial cell layer which is responsible for
secreting a new cuticle after ecdysis.

29. The __________________________________________________ cells of the ommatidia are responsible
for the regulation of how much light enters (or leaves) each unit of the compound eye of arthropods.

30. Many arthropods have centrolecithal eggs; after fertilization, ____________________________________________ leads to the gradual development of an embryo in the periphery of the egg (this is very unlike  development in other Protostomes).
 
 
 

Multiple choice.  Place a circle around the best answer for the following multiple choice questions.  If you believe that
there are two correct answers place a "#1" next to the answer that is most correct, and a "#2" next to the answer that
is nearly correct.
 
1.  The blood of annelids is generally referred to as a storage blood because
A. it is not found in the blood vascular system, but only in the coelom.
B. fats and lipids are also found here.
C. undigested waste material build up in the blood, and is periodically dumped to the outside via metanephridia.
D. the curve for oxygen binding is shifted to the left where oxygen in the outside medium is relatively depleted.
 
2.  In selective deposit feeding polychaetes
A. material adheres to mucous secretions on the surface of feeding structures and is then conveyed to the mouth along
ciliated tracts or grooves.
B. the body shape is generally referred to as primitive.
C. the proboscis is generally well developed to that the worm can switch to another trophic life style when sediment
becomes scarce.
D. all of the above.
 
3. An amphinomid polychaete commonly is called the fireworm
A. because it literally glows in the dark.
B. because of its symbiotic relationship with firecoral.
C. since the setae are numerous and inject an irritating toxin into an intruder.
D. all of the above.
 
4. Torsion in gastropods is a phenomenon which results in
A. a spiralling shell being formed in order to accompany more body mass.
B. the movement of the mantle cavity from the posterior to the anterior portion of the body.
C. the eventual loss of the ganglionic nervous system in these mollusks.
D. none of the above.
 
5. The reduced coelom of molluscs
A. is located principally in the area of the heart.
B. also serves as a place where fluid is filtered into the metanephridium.
C. appears to be related to the lack of segmentation.
D. all of the above.
 
6.  The monoplacopheran Neopilina
A. literally sat on a shelf for nearly 20 years before Lemche recognized it as an example of a "living fossil" of extreme
importance to our understanding of the origin of molluscs.
B. unfortunately, seems to lack the segmentation necessary to relate it to ancestral molluscs.
C. is actually an advanced chiton which has only one shell.
D. none of the above.
 
7. The dorsal cerata of many nudibranchs
A. aid in expanding the surface area of the beast for increased nutrient production by the enclosed zooxanthellae.
B. are really primitive gills since this group has lost its shell.
C. contain secondarily acquired nematocysts that are actually used in defense by the sea slug.
D. is a mouth structure that is used in feeding on hydroid cnidarians.
 
8. The pulmonate snails have lost their gill
A. yet many species have returned to both fresh water and shallow marine waters.
B. but this doesn't stop them from adapting to terrestrial habitats.
C. and many have become hermaphroditic.
D. all of the above.
 

Supply the best word to complete the following sentences:
 
1.  The membranous structures in annelids which extends from both the dorsal and ventral region of the body wall,
and which serves to support the gut in the coelom, are called _____________________________.
 
2.  The fast or startle reflex seen in annelids is a result of activation of the __________________ _________________.
 
3.  Chaetopterus is an example of a worm that builds a U-shaped tube in the mud and then removes food particles
from the water by _____________________________.
 
4.  With regard to reproduction, oligochaetes differ markedly from polychaetes in the these land dwelling worms are
_______________________________ instead of being dioecious.
 
5.  Gills are relatively rare in oligochaetes because oxygen simply __________________________ thru the body wall.
 
6. The structure in many hermaphroditic animals which stores sperm produced by the donor "male" partner, and not
by the receptor "female's" testis, is generally called a __________________________.
 
7. Three features which distinguish molluscs from other phyla are: ________________________,
________________________, and __________________________.
 
8. The outermost layer of the shell of molluscs, which is generally made of a tough protein material and which often
give the animal its colour, is called the _________________________.
 
9. The __________________________ system of pulmonate snails looks remarkably like that of turbellarian
flatworms.
 
10. The beautiful _____________ shells of the tropics are one of the most dangerous of all invertebrates because of
the toxin that it produces.
 
11. The ___________________ of neogastropods is an extension of the buccal mass that allows this snail to move
through soft sediments, yet still be in contact with the water.