Invertebrates - Mollusca

Question 1

what are the characteristics of mollusks?

Answer 1

-coelomate, protostomes
-open circulatory system
-have a hemoceol: spaces between organs for blood to circulate

Question 2

what are the notable parts of mollusks?

Answer 2

-foot: a muscle used for movement, usually what you eat
-visceral mass: contains all internal organs
mantle: fold of tissue, secretes shell if present. if not, may form a cavity
-radula: a strap-like organ for feeding

Question 3

what type of gut do mollusks have and where are they found?

Answer 3

-mollusks have a complete digestive system
-found in marine, freshwater, and terrestrial habitats
-most have a hard shell and have separate sexes, though some are hermaphroditic

Question 4

what are the traits of the class polyplacophora and what type of animal is this?

Answer 4

-chitons: marine only habitat
-eat algae with a radula
-contain 8 dorsal plates make of calcium carbonate

Question 5

what are the traits of the class gastropoda and what type of animal is this?

Answer 5

-snails, slugs, limpets
-marine, freshwater, and terrestrial
-contain torsion: anus above the head, helps with shell position

-contain radula for feeding and eat by grazing or by predation
-have a spiral shell and a collection of sensory organs at the head: cephalization

Question 6

what type of animal is a bivalvia and what are their characteristics?

Answer 6

-clams, oysters, mussels, scallops
-marine and freshwater habitats, have shells with 2 halves of “valves”

-suspension feeders with no head/radula

Question 7

what type of animals are cephalopoda and what are their characteristics?

Answer 7

-squids, octopus, cuttlefish, nautilus
-have beaklike jaws, feed through predation
-shell is reduced or missing entirely, except for the nautilus

-closed circulatory system: blood remains separate from fluid in body cavity
-nervous system with a brain, very smart