Mollusks Flashcards
What phylum are mollusks?
Mollusca
What kingdom are mollusks?
Animalia
What is a class Gastropoda ex)?
Snail
What is a class pelecypoda ex)?
Clam
What is an ex) of class cephalopods?
Squid
Describe the body of a mollusk?
Soft
Unsegmented body
Where is the Mantle?
Grows from ventral wall
What does the mantle do?
Covers and protects visceral mass
Secretes the shell
Visceral mass
Digestive, circulatory, respiratory, reproductive organs
Muscular foot?
Used for locomotion
Highly adapted
What is the epidermis covered with?
Mucus glands and cilia
What kind (broad) of organs does a mollusks have???
Well developed sense organs
Radula
Rasping tongue
Scrapes food
Mantle cavity
Space between mantel and visceral mass
How many shell layers do mollusks have?
3 layers
Periostracum
Outer and protective layer
Prismatic
Middle layer and thickest part
Nacreous
Inner layer
Secretes the mother of pearl
Class Gastropoda aka?
Stomach foot
Univalves
Univalves
One shell
How do Gastropoda move?
Glide on flat foot
Gastropoda shell?
One or no shell (univalve)
Where do Gastropoda live?
Aquatic and terrestrial
How do Gastropoda eat?
All eat using radula
( herbivores, scavengers, predators)
Torsion
Mantle cavity twists due to shell & results in fouling
Fouling
Wastes wash over gills cause anus to be above head
Coiling
Spiraling and winding of body allows Gastropods to hold shell off to the side so they are not crushed by the weight of the shell
Monoecious Gastropoda
Exchange spermatophores
Spermatophores
Sperm packets
Dioecious Gastropodas
Perform many courtship ritual forms
Gastropoda examples
Snails
Slugs
Nudibranchs
Conchs
Cone shells
Class pelecypoda examples
Clams
Scallops
Mussels
Geoduck
Pelecypods basics
Bivalves
Hatchet food=diggers
Hinge ligament of pelecypoda
Two shells (bivalves) held together
Hatchet food
Shovel shaped foot used for digging into sand, very limited locomotion
What type of feeders are pelecypoda?
Suspension feeders
Suspension feeders
No radula
No cephalization
What does the cola on gills create in class pelecypoda?
A current that draws food and water into incurrrent siphon
What type of foot does class cephalodpod have?
Head-foot
Class cephalopod are..
All marine
All are active predators
Foot is modified into tentacles that are concentrated at the anterior end
What is up with class cephalopods shell?
They have no shell or greatly reduced internal shell
Cephalopods examples
Squids
Octopus
Cuttlefish
Chambered nautilus
What is the squid’s pen function?(vestigial internal shell)
To support muscular tissues and organs
