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| 1 | Some descendants of Precambrian acoelomate organisms evolved a more elegant arrangement for a body cavity: a fluid-filled space within the mesoderm, called the coelom. A true coelom means that the space was lined with mesoderm and that mesodermal membranes, the mesenteries, suspended the organs. |
 | A) | True |
| B) | False |
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| 2 | Which of the following is NOT true about the Mollusca? |
| A) | They are all protostomes |
| B) | They all have an “open” circulatory system |
| C) | They all have a muscular foot or modified foot of tentacles and arms |
| D) | They all have a mantle |
| E) | All of the above are correct |
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| 3 | The uniquely derived rasping tongue of the Mollusca is called the… |
| A) | Radula |
| B) | Odontophore |
| C) | Mastax |
| D) | Buccal cavity |
| E) | None of the above is correct |
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| 4 | Which of the following is found in the shell secreted by the mantle of a mollusc? |
| A) | Periostracum (outer organic layer, composed of conchiolin) |
| B) | Prismatic layer (prisms of calcium carbonate in a protein matrix) |
| C) | Nacreous layer (continuously secreted by the mantle) |
| D) | All of the above are found in mollusc shells |
| E) | None of the above is correct |
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| 5 | Which of the following is NOT a class of the Phylum Mollusca? |
| A) | Monoplacophora |
| B) | Polyplacophora |
| C) | Scaphopoda |
| D) | Gastropoda |
| E) | Entoprocta |
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| 6 | Which of the following is mismatched? |
| A) | Gastropoda—snails, slugs, sea hares, etc. |
| B) | Bivalves—clams, mussels, etc. |
| C) | Scaphopoda—chitons |
| D) | Cephalopoda—“head-foot” |
| E) | All of the above are correct |
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| 7 | Of all the Mollusca, only gastropods undergo torsion. |
| A) | True |
| B) | False |
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| 8 | Where would you place a creature that has the following characters: can burrow in sediment; moves by means of “clapping” two valves together, lacks a radula; eyes with a retina; shell with an umbo? |
| A) | Bivalvia |
| B) | Pulmonata |
| C) | Gastropoda |
| D) | Amphineura |
| E) | Polyplacophora |
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| 9 | The coelom of Mollusca is reduced to a partial coelom around the gonads, the kidneys, and the heart (the pericardial membrane). |
| A) | True |
| B) | False |
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| 10 | The ctenidium is the molluscan….. |
| A) | Circulatory system |
| B) | Excretory system |
| C) | Mantle |
| D) | Gill |
| E) | None of the above is correct |
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| 11 | A potentially disastrous ecological event occurred when ____________were introduced into the Great Lakes. |
| A) | Leeches |
| B) | Boring clams |
| C) | Zebra mussels |
| D) | Shipworms |
| E) | Jumbo Umbo clams |
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| 12 | The cephalopods are renowned for their amazing invertebrate intelligence. |
| A) | True |
| B) | False |
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| 13 | Octopods are capable of observational learning by observing one another. |
| A) | True |
| B) | False |
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| 14 | In the squids, most of the shell has disappeared, leaving only a thin, horny strip called the pencil. |
| A) | True |
| B) | False |
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| 15 | Diversity among mollusks is related to their adaptations to different habitats and modes of life. |
| A) | True |
| B) | False |
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| 16 | There is both embryological and molecular evidence that the Mollusca share a common ancestor with the annelids, even though there is debate as to where mollusks arose within the lophotrochozoa. |
| A) | True |
| B) | False |
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| 17 | The Mollusca range in size from almost microscopic to the giant squid Architeuthis with a body and tentacle length nearly 100 meters in length. |
| A) | True |
| B) | False |
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| 18 | Which of the following are suitable habitats for members of the Mollusca? |
| A) | Terrestrial |
| B) | Freshwater |
| C) | Marine |
| D) | Estuary |
| E) | All of the above are suitable for some members of the Mollusca |
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| 19 | Which of the following is NOT correct? |
| A) | The Mollusca have metanephridia for a circulatory system |
| B) | Molluscan larvae are primitively a trochophore, but many have a veliger larvae and some have direct development |
| C) | The molluscan coelom is reduced |
| D) | The cephalopods have the most highly developed molluscan sensory organs |
| E) | All of the above are correct |
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| 20 | Cephalopods swim by forcefully expelling water from the mantle cavity through a ventral funnel, like jet propulsion. |
| A) | True |
| B) | False |
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| 21 | Which of the following is NOT correct? |
| A) | Members of the Class Caudofoveata are wormlike, marine organisms, mostly burrowers. |
| B) | Members of the Class Solenogastres are marine, wormlike, shell-less molluscs with calcareous scales or spicules in their integument |
| C) | Members of the Class Monoplacophora are all extinct |
| D) | Members of the Class Polyplacophora are called chitons; they are dorsoventrally flattened and have eight articulating limy plates |
| E) | The mantle of scaphopods is wrapped around the viscera to form a tube. |
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| 22 | Which of the following is mismatched? |
| A) | Operculum—an opening in the shell of a gastropod |
| B) | Torsion—a phenomenon that moves the mantle cavity and twists the visceral organs |
| C) | Coiling—a spiral winding of the shell and visceral mass, different from torsion |
| D) | Conotoxins—a venom with peptides specific for the neuroreceptors of its preferred prey |
| E) | Ctenidium—carries out respiration activities in many gastropods |
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| 23 | Pulmonate snails have a highly vascularized area in the intestines that serves as a lung. |
| A) | True |
| B) | False |
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| 24 | Which of the following is among the ecologically most jeopardized groups of molluscs in this country? |
| A) | Squid |
| B) | Terrestrial gastropods |
| C) | Freshwater bivalves |
| D) | Opisthobranchs |
| E) | Zebra mussels |
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| 25 | In most freshwater clams fertilization is internal and the fertilized eggs develop into glochidia. |
| A) | True |
| B) | False |
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| 26 | The early nautiloid and ammonoid shells were heavy but made buoyant by a series of gas chambers connected by a cord of living tissue called a… |
| A) | Carbuncle |
| B) | Siphuncle |
| C) | Nephridium |
| D) | Funnel |
| E) | Branchial nerve cord |
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| 27 | An ink sac that empties into the rectum of many cephalopods contains an ink gland that secretes sepia, a dark fluid containing the pigment melanin. |
| A) | True |
| B) | False |