Phylum Mollusca:Mollusks
Traits: Soft bodies, invertebrates, mantle-covers organs, produces the shell,
foot-helps with movement.
Classes of Mollusks:
Gastropods: Snails & Slugs: have an extra mucus layer to help
move; use radula to eat.
Bivalves: Clams, Mussels, Oysters, and Scallops: get food by filter
feeding; two shells held together by a tough muscle.
Cephalopods: Squid, Octopus, Nautilus, and Cuttlefish: Aggressive
hunters-sharp beak, adaptation of foot into tentacles, move by jet propulsion,
release ink when scared.
Phylum Arthropoda:Arthropods
Traits: Jointed appendages(legs, antenna, and wings); segmented bodies;
exoskeleton(hard, outer covering which is shed(molting) in order to grow.
Classes of Arthropods:
Millipedes: 4 legs per body segment, rounded bodies, plant eater-sucks
plant juices, give off a nasty odor.
Centipedes: 2 legs per body segment, flat bodies, very aggressive hunters,
poison and claws.
Crustaceans: most live in the water, use gills to breathe, 2 pairs of
antennae, 2 or 3 body segments, 5 or more pairs of legs. Examples: Crabs,
shrimp, crayfish, lobster, copepods.
Arachnids: some silk to make webs, have venom; 8 legs, 2 body
parts(head and abdomen), no antennae, can be parasites. Examples:Spiders,
ticks, scorpions, and mites.
Insects: 3 body parts-head, thorax, and abdomen; one pair of
antennae(sense organs), 6 legs, most have two pairs of wings. Life cycles:
complete metamorphosis-egg, larvae, pupa, and adult or incomplete
metamorphosis-egg, nymph, adult. Insects molt to grow. They are successful
due to their small size, their ability to hide, mimic, and camouflage, production
of a large number of offspring, adapted mouthparts, and flight. Insects are
extremely important on the food chains of many organisms and can help control
other pests(biological control).
Phylum Echinodermata:Echinoderms
Traits:spiny-skinned, water vascular system, tube feet, and radial symmetry.
Examples: Starfish, sea star, sand dollar, sea urchin, and sea lilies.
Invertebrate Test Guide
Additional Concepts:
Symmetry, Asexual Reproduction, Sexual Reproduction, four functions of
animals, parasite/host relationship, and levels of organization.
Phylum Porifera:Sponges
Traits: Simplest group of animals, organized only to cellular level, bodies
covered by pores(tiny openings) that allow water containing nutrients and
oxygen to enter the sponge, filter feed, live in water-water current
necessary for survival.
Examples: Sponges
Phylum Cnidaria:Cnidarians
Traits: Stinging cells used to kill prey(nematocysts); two body
forms:polyp and medusa; live in water; developed to tissue level, some
have radial symmetry.
Examples:Jellyfish, Sea Anemones, Hydra, and Coral.
Worms:
Phylum Platyhelminthes:Flatworms
Traits:flat bodies, one opening(mouth), parasitic, can regenerate, simple
body design.
Examples:Planaria and tapeworm
Phylum Platyhelminthes:Nematoda
Traits:round bodies-like a piece of spaghetti with pointed ends, open
circulatory system, one-way digestive system.
Examples:Trichinella, heartworm, hookworm.
Phylum Platyhelminthes:Annelida:Segmented Worms
Traits:One-way digestive system; two openings(mouth and anus),
developed to system level, closed circulatory system(network of blood
vessels). Earthworms are beneficial:loosen and fertilize the soil.
Examples:Earthworm and sandworm.