Phylum Molluska Flashcards
Taxonomy for Phylum Molluska:
Kingdom Animalia Subkingdom Bilateria Division Protostomia Superphylum Lophotrochozoa Phylum Molluska
Class Gastropoda Synapmorphies
Asymmetric Coil
Torsion
Class Cephalopoda Synapomorphies
Symmetric Coil Shell Chambered Beak like radula Food divided into arms Mantle folded as single siphon Siphuncle
Class Bivalva Synapomorphies
Shell with 2 hinged valve
Mantle folded as double siphon
Class Scaphopoda Synapomorphies
Shell with 1 tubular valve
Captaculae
Classes Gastropoda and Cephalopoda Synapomorphies
shell with 1 coiled valve
Class Polyplacophora synapomorphies
shell with 8 valves
Class Monoplacophora Synapomorphies
Shell with 1 conical valve
Classes Monoplacophora, Gastropoda, Cephalopoda, Bivalva, and Scaphopoda Synapomorphies
Shell 1-2 valves Shell with 3 layers 1) Periostracum 2) Ostracum 3) Hypostracum
Phylum Molluska Synapomorphies
Preoral Tentacles - come off around mouth
Radula - feeding
Muscular Foot - locomotion
Mantle - tissue that makes shell
Classes Gastropoda, Cephalopoda, Bivalva, and Scaphopoda Synapomorphies
Internal Gills surrounded by mantle
Classes Bivalva and Schophoda synpomorphies
Decephalized
Mantle envelopes entire body
Additional Features of Phylum Molluska
Triploblastic
Cephalized
Bilaterally Symmetric
Eucolemate
Class Polyplacophora (Katharina tunicata)
Usually Dioecious
Algivore
Prograde or retrograde locomotion
Marine only habitat
Prograde or retrograde locomotion definition
Prograde: Direction of movement and direction of muscular wave are the same direction
Retrograde: Direction of movement and direction of muscular wave are in different directions.
Class Monoplacophora (Patella vulgata) features
Dioecious
Aligivores
Prograde or retrograde locomotion
Marine only habitat
Class Gastropoda (Helix aspersa) features
Dioecious or monoecious
Algivores
Prograde or retrograde locomotion
Marine, fresh water, or terrestrial habitats
Torsion means what for Class Gastropoda?
The body turns 180 degress
How do Gastropods protect themselves?
They draw their head in first into their shell due to the organs being near their head. Then they draw in their foot.
Why have some Gastropods have lost their shell?
Due to new defenses they have developed. Like fitting under really tight spaces or shooting ink as a defense mechanism.
Class Cephalpoda features
Dioecious Predacious Closed circulatory system with 3 hearts Complex Eye Chromatophores Complex behavior Variable locomotion Marine Only Habitat
Describe the Circulatory system of a Cephalopod
2 branchial hearts pump deoxygenated blood into the gills
1 systemic heart pumps oxygenated blood into the body
What are chromatophores used for?
Defense, mating, and hunting
