Mollusca Classification

Question 1

Class: many plate bearing: 7-8 separate plate

Answer 1

Polyplacophora

Question 2

organs derived from mantle extending from holes of plates (light receptors or secrete periostracum )

Answer 2

Aesthetes

Question 3

release amylase-containing secretions into the stomach

Answer 3

Pharyngeal/sugar glands

Question 4

A series of eight overlapping and articulating plates covering the dorsal surface

Answer 4

Shell

Question 5

chiton’s thick lateral mantle

Answer 5

Girdle

Question 6

Class: not shell bearing; cylindrical, vermiform body with the foot forming a narrow keel: 300 species in deep ocean: unsegmented: calcareous spines: with radula

Answer 6

Aplacophora

Question 7

Class: one Shell bearing: - 3-6 pairs of ctenidia, 6-7 Pairs nephridia, 20 extant species; unhinged limpet-shaped shell

Answer 7

Monoplacophora

Question 8

Class: stomach foot: 90-180 degrees (torsion), Proteinaceous shield on the foot (operculum)

Answer 8

Gastropoda

Question 9

Some, parthenogenetic, Some are protandric hermaphrodites : sex of a single individual changes from male to female with age, some prosobranchs and opisthobranchs,

Answer 9

Gastropods

Question 10

Torsion in Gastropods

Answer 10

180 degrees counterclockwise

Question 11

rearranges visceral organs so that they are accommodated inside the coils of the shells

Answer 11

Torsion

Question 12

Reversal of torsion. Takes place during the larval stage and the animals regains bilateral symmetry

Answer 12

Detorsion

Question 13

Subclass: anterior gill, Marine and freshwater snails, Generally free-living and mobile, Predominantly marine Possess a well-developed shell, mantle cavity, osphradium, and radula ,Foot bears a rigid disc of protein called operculum Complete torsion

Answer 13

Prosobranchia

Question 14

Soft, fleshy tube through which water is drawn into the mantle cavity and over the gill

Answer 14

Siphon

Question 15

Function of siphon?

Answer 15

for respiration, locomotion, feeding, and reproduction

Question 16

Subclass: posterior gill. Includes sea hares, sea slugs, bubble shells. Almost all marine <1,100 species described, loss of shell, loss of operculum, loss of mantle cavity, Limited torsion during embryogenesis

Answer 16

Opisthobranchia

Question 17

loss of ctenidia- featherly gills arising from dorsal surface

Answer 17

cerata

Question 18

Order: Sea slugs, Use nematocysts usurped from cnidarian prey from defense

Answer 18

Nudibranchia

Question 19

Produce chemical defenses housed by ?

Answer 19

Cerata

Question 20

Possess ? in the second pair tentacles located dorsally of the head (chemosensors)

Answer 20

rhinophores

Question 21

Order: Sea hares Found in shallow waters and rock pools. Prominent tentacles on the head resemble rabbit ears. Releases defensive secretion ink (purple) and opaline

Answer 21

Anaspidea

Question 22

Order: Sea butterflies, Foot modified to produce wing-like flaps

Answer 22

Pteropoda

Question 23

wing-like flaps called ?

Answer 23

parapodia

Question 24

Function of parapodia?

Answer 24

Swimming

Question 25

Subclass: Mantle cavity is highly vascularized and functions as lungs through an opening. Few are marine; if present, in intertidal zones and estuaries only. Long radula in keeping with herbivorous diet Head bears 2 tentacles. Torsion limited to 90°

Answer 25

Pulmonata

Question 26

functions as lungs through an opening called?

Answer 26

pneumostome

Question 27

chitinous or calcareous accessory organ that are thrust into the partner during mating among pulmonate gastropods

Answer 27

Love dart

Question 28

Class: Two-valved shells .Body is flattened laterally >15,000 species including clams, scallops, mussels, and oysters . Primarily marine, but about 10-15% are in freshwater Hinged shell, the 2 valves are joined by springy ligament.

Answer 28

Bivalvia

Question 29

Subclass: plate gill. Includes familiar bivalves such as clam, mussels, scallops Gills modified to collect suspended food particles Secretion of attachment by byssal or byssus gland in the foot

Answer 29

Lamellibranchia

Question 30

Subclass: fence gill, small group of carnivorous bivalves and on pieces of decomposing animal tissue All very deep marine water Ctenidium highly modified, lacking filamen

Answer 30

Septibranchia

Question 31

Class: spade foot Tusk-shaped, conical shell open at both ends Development of anterior, thread-like adhesive feeding tentacle

Answer 31

Scaphopoda

Question 32

It is a thread like adhesive feeding tentacle

Answer 32

Captacula

Question 33

Class: head foot, Shell divided by septa with chambers connected by siphuncle (yellow arrows) Closed circulatory system, Derivatives of the molluscan foot are the siphon, arms and tentacles (8-10) Possess two eye

Answer 33

Cephalopoda

Question 34

Subclass: Soft-bodied, shell-less cephalopods

Answer 34

Coleoidea-

Question 35

It is the colored cells

Answer 35

Chromatophores

Question 36

It is the reflective cells

Answer 36

Iridocytes

Question 37

It is known to be light organs

Answer 37

Photophores

Question 38

Male octopi have ?

Answer 38

hectocotylized arms

Question 39

In subclass coleoidea it has an ? Discharged through anus

Answer 39

ink sac

Question 40

It is a highly modified arm that transfers spermatophores

Answer 40

Hectocotylus

Question 41

It is known to be the packets of sperms

Answer 41

Spermatophores

Question 42

Subclass: Nautilus 5 or 6 species possessing true shell. Cameral fluid in chambers. Septa penetrated by siphuncle

Answer 42

Nautiloidea

Question 43

calcified tube with enclosed strand of vascularized tissue

Answer 43

siphuncle