Mollusca terms & definitions

Mollusca: organization

tissue and organ level

Mollusca: embryonic development

tripoblastic

protostome

eucoelomate

Mollusca: Symmetry

bilateral

Mollusca: skeleton

exoskeleton

hydrostatic skeleton

mollusca exoskeleton

CaCO2 shell secreted by mantle

Mollusca skeleton exception

Order Octopodiformes

Mollusca: movement

muscular foot or jet propulsion

Mollusca: sensory/nervous

cephalization

complex sense organs (eyes, cerebral ganglia)

Mollusca: digestion/feeding

complete gut: digestive system with two holes (mouth and anus)

Radula: feeding

Which mollusca class do not have radula

Bivalves

Mollusca: excretory

metanephridia

mollusca: circulation

open circulatory system

Which class of mollusca have a CLOSED circulatory system

cephalopods

Mollusca: respiration

gills

Which class of mollusca do NOT have gills

Pulmonata

What do Class Pulmonata have instead of gills

a modified mantle that acts like lungs

Mollusca: reproduction

asexual or sexual

monoecious or dioecious

internal and external

Four body regions of Phylum Mollusca

head, foot, visceral mass, mantle

contains sensory organs (eyes and ganglia) and muscles

head

muscular (usually for locomotion)

foot

all the innards (digestive reproductive, and circulatory organs)

visceral mass

epidermal layer that covers all of visceral mass, delimits the name cavity; this also secretes shell, in those species that have one

mantle

Digestion/Feeding: Polyplacophora

herbivore

Digestion/Feeding: Gastropoda

mixed

Digestion/Feeding: Scaphopoda

deposit feeder

Digestion/Feeding: Bivalvia

filter feeding

Digestion/Feeding: Cephlapoda

carnivore

rasping mouthpart used for cutting or scraping

radula

Chitinous ribbon with minute teeth

radula

What is this

head and radula

What is this

radula

What is 1

mouth

What is 2

radula

what is 3

radula teeth

what are these

radula

blood flows through the body cavity

open circulatory system

blood flows in a closed loop of vessels

closed circulatory system

“nudi”

naked

“branchs”

gills

“pulmonates”

with lungs

gills are outside of their body

heterobranchs (nudibranchs)

what is this

gills

what is this

gills

what is this

vascularized mantle

what is this

blood vessels of the lung

What is the term for how molluscs filled many unoccupies niches and took over many occupied niches from existing marine animals

adaptive radiation

Which class became sessile filter feeders

bivalves

Which class(es) are primarly grazers

chitons and snails

Which class are active predators

cephalopods

What are the 5 classes of Phylum Mollusca

1.Polyplacophora

2.Gastropoda

3.Scaphopoda

4.Bivalvia

5.Cephalopoda

What are the Subclasses to class Gastropoda

1.Prosobranchia

2.Heterobranchia

What are the infraclasses to Subclass Heterobranchia

1.Euthyneura

2.Pulmonata

What are the subclasses to class Cephalopoda

1.Ammonoidea

2.Nautilodea

3.Coleoidea

What are the orders of subclass Coleoidea

1.Octopodiformes

2.Decapodiformes

What class do chitons belong to

Polyplacophora

Which class of Mollusca live in the intertidal zone on rocks and are grazers

Polyplacophora

How many separate shell plates or valves does class polyplacophora have

eight

What is the point of 8 separate shell plates or valves

allows flexing upward and curling into a ball

marks separation between foot and mantle

pallial groove on ventral surface

Which class of Mollusca contain snails and slugs

Gastropoda

Which class is aquatic and terrestrial and contain 80% of all living molluscs

gastropoda

coiling creates a spiral in 3 dimensions

conispiral

coiling occurs in a single plane

thought to be ancestral

planispiral

Which class and subclass consists of shelled (mostly marine) aquatic snails

Class Gastropoda

Subclass Prosobranchia

Which class and subclass have operculum and often have large shells that are mainly conispiral

Class Gastropoda

Subclass Prosobranchia

hard covering over aperture

operculum

Which class and subclass includes gastropods with a gill origin different from that of other gastropods (sometimes on the outside of the body)

Class Gastropods

Subclass Heterobranchia

Which class and subclass include marine, freshwater, and terrestrial snails and slugs

Class Gastropoda

Subclass Heterobranchia

Which class and subclass have very reduced shell or no shell

Class Gastropoda

Subclass Heterobranchia

Which class, subclass, and infraclass has marine, freshwater slugs and very reduced shell or no shell?

Class Gastropoda

Subclass Heterobranchia

Infraclass Euthyneura

Which infraclass includes land snails and slugs

Pulmonata

Which infraclass have vascularized mantle

pulmonata

Which infraclass includes land snails and slugs that have small shells without operculum (can be planispiral or conispiral)

Pulmonata

Which class does tooth or tusk shells belong to

Scaphopoda

What class is the only group to be exclusibely infaunal

Scaphopoda

live within the sediment rather than on top (epifaunal) with mouths downward

infaunal

Which class has clams, oysters, scallops, and mussels

Bivalvia

Which class rely on flow of water for food (filter feeder) and waste excretion

bivalvia

Which class has no radula and the gills in this group have multiple functions: feeding, reproduction and respiration

bivalvia

Which class contains many that have poorly developed senses

bivalvia

name for the oldest part of the shell

umbo

Which class contains squid, octopods, and nautilus and ammonites

cephalopoda

Which class have reduced shells (1 extant genus with shell)

cephalopoda

Class Cephalopoda defense mechanisms

jet propulsion

chromatophores

ink sacks

used for camouflage or warning signs

chromatophores

What type of circulatory system do Class Cephalopoda have

closed circulatory system

Which class has well developed senses and nervous system

cephalopoda

Which class and subclass contains ammonites (all extinct with extensive fossil record)

Class Cephalopoda

Subclass Ammonoidea

Which class and subclass have shells with distinctive sutures that markes where the septa joined the shell wall

Class Cephalopoda

Subclass Ammonoidea

This class and subclass includes animals that are scavengers and predators of small animals in coral reefs

Class Cephalopoda

Subclass Nautoloidea

What is the only living cephalopod with an external shell

nautilus

What help nautilus stay buoyant

internal chambers

Which class, subclass, and order contain squid and cuttle fish, organisms with 8 arms + 2 addition tentacles, that are active swimmers

Class Cephalopoda

Subclass Coleoidea

Order Decapodiformes

What reduced shell do cuttlefish have

cuttlebone

What reduced shell do squid have

pen

What class, subclass, order includes octopuses and vampire squid that are found in all marine habitats

Class Cephalopoda

Subclass Coleoidea

Order Octopodiformes

Which order of subclass coleoidea have no shell

octopodiformes