Phylum Mollusk

Question 1

Mollusks

Answer 1

“soft body”

Question 2

Shared traits

Answer 2

Muscular foot
Visceral mass
Mantle, gills, radula
Trochophore -> Veliger (larvae)

Question 3

Characteristics

Answer 3

Bilateral, triploblastic
Eucoelomates (reduced, but still 1st)
Organ system (complete digestive system)
Hemocoel and hemolymph (blood mixes with body fluid which give it different classification)
Open circulatory system

Question 4

Shells

Answer 4

Most have shells of CaCO3
Why there is an extensive fossil record
Mantle deposits calcium carbonate (CaCO3)

Question 5

Radula

Answer 5

Rasping tongue/drilling tool/venomous harpoon
Modified into a beak

Question 6

Molluscan diversity

Answer 6

8 classes, only need to know four
Chiton
Snails
Cephalopods
Bivalves

Question 7

Gastropoda

Answer 7

“Stomach foot”
Snails, slugs, nudibranchs
Most diversity in phylum
Torsion -> body twisting during development

Question 7

Polyplacophora

Answer 7

“many plates” [8 plates make up dorsal shell]
Chitons
Marine

Question 8

Bivalvia

Answer 8

“two halves”
Oysters, clams, mussels, scallops
Filter feeders

Question 9

Cephalopods

Answer 9

“Head foot”
Squid, octopus, cuttlefish, nautiluses
Mostly reduced shell (or is completely absent)
Radula -> beak
Closed circulatory system
Large, “camera” eye
Complex nervous system