Phylum Mollusca

Label the structure

1. Foot 2. Valve 3. Growth range 4. Siphons 5. Umbilical 6. Hinge ligament

Label the structures

7. Heart 8. Intestine 9. Shell 10. Mantle 11. Posterior abductor muscle 12. Excurrent siphons 13. Incurrent siphon 14. Anus 15. Gills 16. Gonad 17. Foot 18. Palps 19. Mouth 20. Stomach 21. Digestive gland 22. Anterior adductor muscle

These powerful muscles are used to open and close the valves

Adductor

Members of this class have bilateral symmetry

All

Opening leading out of the digestive system

Anus

Body symmetry in which the right and left sides mirror one another

Bilateral

What class of mollusk has no distinctive head

Bivalve

What class of mollusk swim by jet propulsion

Bivalve (only scallops), cephalopods,

What class of mollusk are all marine species?

Bivalve, cephalopods, chitons

What class of mollusk all use gills for both respiration and food collection?

Bivalves

Describe the difference in feeding methods among gastropods cephalopods and bivalves

Bivalves eat by filter feeding by the gills Gastropods can eat on algael kelp , extend proboscis to find food , and are Scavengers , deposit , and filter - feeders . Cephalopods use tentacles larms + beak like jaws tradulas to eat food

All species in this class have two shells

Bivalvia

What class do clams, oysters, scallops, and mussels belong to?

Bivalvia

What class does a clam belong to

Bivalvia

Members of this class are filter feeders

Bivalvia and Cephalopoda

Members of this class have a trochophore larva

Bivalvia, Gastropoda

What class of mollusk have a pair of tentacles on their head

Cepha

What class of mollusk are known for their great camouflage abilities?

Cephalopod

What class of mollusk bite prey with a beak

Cephalopod

What class of mollusk has a closed circulatory system

Cephalopod

What class of mollusk have all carnivorous species?

Cephalopod

What class of mollusk is intelligent, with a well-developed nervous system

Cephalopod

Animals in this class have a closed circulatory system

Cephalopoda

Most members of this class have no shell

Cephalopoda

The members of this class are free swimming predators

Cephalopoda

This class contains animals whose foot is divided into arms and tentacles

Cephalopoda

This class has the most advanced nervous system

Cephalopoda

What class do squid, octopus, nautilus, and cuttlefish belong to?

Cephalopoda

What class of mollusk has a shell that contains 8 overlapping plates on the dorsal surface

Chiton

Colour changing pigment cells that provide camouflage to cephalopods

Chromatophores

These structures help direct food into the mouth

Cilia

Secretes enzymes responsible for the speedy digestion of food

Digestive gland

Structure through which water and wastes leave the clam

Excurrent siphon

Mollusks are divided into classes based on the characteristics of their foot .

False , valves / shell

All members of the phylum Mollusca have radial symmetry .

False bilateral

A flexible tongue - like structure with abrasive teeth that point backward is called a chromatophore

False radula

Bivalves are the only molluscs that do not possess a foot .

False, all molluscs have a foot

The fertilized egg of a clam develops into a pinnula larva

False, trocophore larvae

Feeding strategy used by bivalves

Filter feeding

Describe the foot of a gastropod

Flat + strong

This muscular structure is used for burrowing into the sand

Foot

Describe the foot of a bivalve. What purpose does it serve? How is this foot adapted for its purpose?

Foot is ventrally located and is used for burrowing and locomotion. Foot retractor muscles to move the foot

What class of mollusk undergo torision

Gastropod

What class of mollusk have external shells present in some species

Gastropod & cephalopod (nautilus)

What class of mollusk use radula in feeding

Gastropod, cephalopod, chitons

Members of this class have most species having only one shell but some have none

Gastropoda

What class contains snails, slugs, and nudibranchs

Gastropoda

What class do nudibranchs, snails, and slugs belong to?

Gastropoda

Members of this class have an open circulatory system

Gastropoda and bivalvia

What classes of mollusk have an open circulatory system?

Gastropoda, bivalve, chiton

What class of mollusk use excretory structures called nephridia

Gastropoda, bivalves, chitons

Members of this class have a radula

Gastropoda, cephalopoda

members of this class have a body plan consisting of a head, foot, and visceral mass

Gastropoda, cephalopoda

What class do snails belong to?

Gastropods

Structures found in aquatic molluscs that are specialized for gas exchange

Gills

Structures that are responsible for absorbing oxygen from the water

Gills

Name given to sex organs

Gonads

This pumps blood through the open circulatory system

Heart

This structure connects the two valves

Hinge

Structure through which water, food, and oxygen enter the clam

Incurrent siphon

What kind of shell does a squid have?

Internal degenerate shell

Area where digested food is absorbed into the blood

Intestine

Layer of soft tissue that covers the visceral mass

Mantle

Thin layer of epidermal tissue that covers the visceral mass

Mantle

Describe the foot of a cephalopod

Modified to be arms that extend from the head

What roles do molluscs play in the ecosystem ? State 3 examples source

Molluses are an important food source for birds , mammalls and more predators , filter the water , and play a key role in Soil regeneration and nutrient reycling .

What is the composition of a mollusc shell ? What are the different layers of a mollusc shell ? How is the shell made ? What structure ( s ) help to make the shell ?

Mollusks are made up of calcium carbonate shells , it issecreted by the mantle . The 3 layers are the peristracum Prismatic , Nacreous

List and describe the three main parts of the molluscan body plan

Mollusks have a nead , visceral mass , and a foot The head contains sensory organs visceral mass contains organs and the foot isused for locomotion

What are some of the other animals in bivalvia

Mussels, oyster, scallops

What is the inner most layer of the shell

Nacreous layer. Nicknamed the mother of pearl layer. Made of calcium carbonate

What is the only cephalopod to retain its external shell?

Nautilus

List three or more ways the nautilus is different from other cephalopods

Nautilus have a largecoiled shells of chambers with senta . Their head has 60-20 tentacles coated wisticky substances . They dwell on the bottom during the day and float closer to the surface at the night .

What are some other animals in the cephalopod class

Octopus, squid, cuttle fish

The opening into the digestive system

Palps

What class do chitons belong to?

Polyplacophora

What is the second layer of the shell

Prismatic layer made up of calcium carbonate and protein, makes up the bulk of the shell

What class do tusk shells belong to?

Scaphopoda

What are some other animals in the gastropod class

Sea slugs, abalones, cone shell

Made of calcium carbonate and provides protection to the clam

Shell

Structure made of calcium carbonate that protects the soft bodies of some mollusks

Shell

Describe the shell of bivalves

Shell divided into 2 jointed halves

Relate the type of movement with the structure of the foot in the snail , clam , and squid

Squids usejet propulsion and fins Snails propels itself by deforming a layer of mucus beneath it via muscular contractions in its foot muscle Clams burrow w / foot

Site of digestion

Stomach

5. In what ways are cephalopods more advanced than the other classes of molluscs ?

They have a large cylindrical body with 10 appendages ! and apen . They have a closed they have suckers for hunting . circulatory system and

What adaptations allow cephalopods to be excellent predators ?

They have a ring of tentacles , internal and suckers . Also have clark fluid sepia , to that degenerate shells ( pen ) , is a good weapon + distractar .

How and why do cephalopods change color ?

They have chromatophors which are skin cells for pigment that can alter color and pigments .

The process occurs during gastropod larval development and results in the 180 degree twisting of the visceral mass

Torison

Free swimming ciliated larva found in molluscs

Trocophore

Bivalves lack a distinct head and there are no specialized sense organs

True

Cephalopods have a complex brain and well - developed sense organs .

True

Most clams have separate sexes

True

Nudibranchs are marine gastropods that lack a shell .

True

What shell do gastropods have

Univalve shell

What is the foot of a gastropod used for and how is it adapted for this?

Used for crawling locomotion and it is highly muscular

Shells are known by this name

Valves

what purpose does the foot of a cephalopod serve? How is the foot adapted for this purpose?

capturing prey and locomotion. Suction cups for grabbing prey; long and mobile

Members of this class undergo torison

gastropoda

What is the outer layer of the shell

periostracum made of protein called conchiolin, protects the shell from dissolution and boring animals