The Internal Shell Found in Squid

The Internal Shell Found in Squid

  1. The internal shell found in squid.

Pen

  1. Melanin-containing substance produced by cephalopods and used as a defensive mechanism.

Ink

  1. The twisting that allows gastropods to retract the head into the shell.

Torsion

  1. "Bivalvia" means this.

Two valved hinged shell

  1. The reduced true body cavity that is found in all mollusks.

Coelom – relatively small cavities around the heart, nephridia, gonads

  1. The internal shell found in cuttlefish used for many things.

Powder for polishing, feeding birds (calcium

  1. Mollusk class to which slugs, snails and limpets belong.

Gastropoda

  1. Pigment cells which allow the cephalopods to rapidly change color.

Chromatophores

  1. The oldest portion of the bivalve shell.

Umbo

  1. "Toothed tongue" found in many mollusks and is used for scraping food.

Radula

  1. The structure which secretes the shell.

Mantle

  1. Mollusk class which means "many plates" and contains the chitons.

Polyplacophora

  1. Mollusk class to which clams, oysters and scallops belong.

Bivalvia

  1. The very well-developed structures found in cephalopods.

Nervous system

  1. Minor mollusk class which contains the tusk shell.

Scaphopoda

  1. The siphon, found in bivalves, through which water is filtered IN.

Cilia move water into water tubes through pores in gills. Siphon is extension of mantle

  1. Mollusk class which means "one plate" and consists of mollusks with undivided arched shells.

Monoplacophora

  1. The flap that acts to cover the opening of gastropod shells during danger.

Operculum

  1. Funnel-like structure found in cephalopods used for jet propulsion.

Foot

  1. The siphon, found in bivalves, through which waste is filtered OUT.

Water exits through mantle cavity at dorsal aspect of gills called suprabranchial chamber and through opening in mantle

  1. Region of the mollusk body which contains most internal organs.

Visceral Mass

  1. "Gastropoda" means this.

Stomach Foot

  1. Material which makes up most mollusk shells.

Calcium Carbonate

  1. Type of circulatory system found in all mollusks EXCEPT cephalopods.

Open

  1. Tentacles are a modified version of this region of the mollusk body.

Foot

  1. "Cephalopoda" means this.

Head Foot

  1. Muscles found in bivalves which help to close the shell.

Adductor Muscles

  1. The shell-less class which contains wormlike mollusks.

Aplacophora

  1. Means "soft bodied."

Mollusca

  1. Mollusk class to which squid, octopuses, cuttlefish, and the nautilus belong.

Cephalopod

  1. The external structure that distinguishes the nautilus from other cephalopods.

Shell

  1. Which Phylum are Mollusca most closely related to?

Annelida

  1. List the seven classes of Mollusca

Caudofoveata, aplacophora, polyplacophora, monoplacophora, Scaphopoda, bivalvia, gastropoda, cephalopoda

  1. Give examples of the classes Bivalvia, Gastropoda, and Cephalopoda

(oysters, clams, mussels, scallops) (snails, limpets, slugs) (octopus, squid, cuttlefish, nautilus)

  1. Describe the five characteristics of Mollusca

Body with two parts head-foot and visceral mass, mantle secretes calcium shell covering visceral mass, mantle cavity functions in excretion, gas exchange and elimination of wastes and releases reproductive prodeucts, bilateral symmetry, protostome characteristics – larvae and spiral cleavage and coelom formation, coelem around heart and gonads, open circulatory system (not cephalopods) radula present scraping food

  1. Which of the molluscan classes is the largest

Gastropoda

  1. Describe torsion in gastropods and possible advantages

Without torsion head would enter last, anterior opening in mantle cavity allows for clean water to enter rather than silt, more sensitive to to stimuli in the direction it is moving

  1. What two ways do gastropods move?

Feet with cilia, muscle contraction over foot

  1. Describe how gastropods eat and digest food

Scraping algae or other organisms with radula, digestive tract has cilia moves into stomach and acid is released

  1. Explain the difference between open and closed circulatory systems and which one does gastropods, bivalvia, and cephalopods have

Open (G,B) Closed (C)  A closed circulatory system, found in all vertebrates and some invertebrates, circulates blood unidirectionally from the heart, around the body, and back to the heart.

 An open circulatory system, found in most mollusks, pumps blood into a cavity called ahemocoelwhere it surrounds the organs and then returns to the heart(s) throughopenings.
41. Explain how gastropods procreate

Many are dioecious. Ducts discharge gametes into the sea for external fertilization. Some are monoecious, internal crossfertilization

42.Which is the most complex Mollusca class?

Cephalopoda

43.Describe what kind of shell cephalopoda has had in the past and what most of them have currently.

Ancestral cephalopods had conical shells, Nautilus is only one currently with external shell

  1. How do cephalopods move?

Jet propulsion

  1. Describe the cephalopods eating and digestive process

Locate prey by sight, capture with tentacles with cups,jaws and radula, venom, peristalsis, extracellular, glands produce enzymes

  1. Describe the nervous system of the cephalopod

Brains are large, ganglia, controls muscles, sensory perception, decision making

  1. How do cephalopods procreate?

Dioecious, tentacles intertwine during copulation

  1. Which is the second largest class of Mollusca?

Bivalvia

  1. two convex halves of shells are called

valves

  1. What is the function of the adductor muscles

Close the shell

  1. How much water can an average size oyster filter per hour

Roughly 2 gallons per hour

  1. How do bivalvia procreate

Most are dioecious, some monoecious

51. What is the thin layer of tissue that enfolds the body of all mollusks

Mantle

  1. What type of coelom do members of Phylum Mollusca have?

True coelom

  1. List the three major regions of the mollusk body

Head-foot, visceral mass, mantle
54. In the open circulatory system of most mollusks, blood is found where

Pumps blood into cavity surrounding organs hoemoceal

  1. List 2 class of mollusk that have radulas.

Gastropoda, cephalopoda
56. A terrestrial mollusk which lacks a shell would belong to which of the following classes

gastropoda

  1. While snorkeling on a marine expedition, students observe an active animal that has a series of muscular tentacles bearing suckers and a large head region. Segmentation is not observed, but a pair of large, well-developed eyes is clearly evident. The students have observed an animal belonging to which class

cephalopoda

  1. What is the rasping structure used for feeding in most mollusks

Scraping food

  1. Cephalopods are known for their ability to rapidly change colors upon sensing danger. This is accomplished by what

When muscles attached to pigment cells (chromatophores) contract color changes

  1. What is the Latin for “soft bodied”

mollusca

  1. In shell-containing mollusks, what structure is responsible for secreting the shell

mantle

  1. The shell of most mollusks is composed of what substance?

Calcium

63. The ____visceral mass______is the region of mollusks dorsal to the head-foot and contains the internal organs.

64. In bivalves, what structures work with the gills in order to accomplish filter feeding?

Mantle cavity, cilia

65. What is the oldest portion of the bivalve shell?

umbo

66. The adaptations of bivalves to a sedentary, filter-feeding lifestyle that exploits the sand of a beach habitat, has led to the loss of the ______head______and the _____radula______.

67. In cephalopods, which funnel-like structure helps to propel the animal by rapidly expelling water

mantle

68. What is the Latin of “many plates”?

polyplacophora

69. What is the Latin for “boat foot”?

scaphopoda

70. What is the Latin for “one plate”?

monoplacophora

71. What is the Latin for “without a plate”?

aplacophora

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