Invertebrate Overview

Fill in the blanks using your text and field guide, and you can use the coloring book, as references.

The Phylum Porifera, commonly known as the ____________, has the simplest structure of the major animal phyla. In addition to chemical defenses they have calcium or silica skeletal elements called ____________. They are filter feeders, moving water & food particles in through the __________, through a series of chambers lined with flagellated ___________cells which trap food as well as cause water flow. Water passes out of the sponge through larger pores called ____________. These animals may be vase shaped huge blobs or thin crust and are often brightly colored.

The phylum Cnidaria has a gut which lacks an _________. There are two body forms: the anemone-like _____________ stage and the jellyfish-like _________stage. The Phylum has stinging cells called __________. The Class _____________ includes the anemones and corals. The Class ____________ includes the true jellyfish. The third Class, Hydrozoa, includes the benthic ______________ as well as fire coral and man-o-war.

Flatworms belong to the phylum ______________________. Nemerteans or ribbonworms, differ from flatworms by having a _____________ gut. Peanut worms, Sipunculids are _______________ feeders. The best known Echiuran worm, the fat innkeeper worm lives in a burrow with these four commensals (Common names OK): a ______________, a ___________, a_____________ & a ______________.

Within the Phylum Annelida are the terrestrial earthworms and the marine Class ________________. This class includes many free moving (errant) bristleworms such as the Genus __________________. It also includes many sessile tube dwellers such as the Genus _________________________.

Bryozoans (Ectoprocts) are colonial animals who feed using a horseshoe fan structure called a ________________. Each individual clone or _____________ lives in a little box and many are specialized for special tasks such as feeding defense or reproduction. Some species resemble hydroids. Jack Frost bryozoan forms white splotches on kelp.

The phylum Mollusca includes soft bodied animals who typically have a hard CaCO₃

shell. The______________, Polyplacophora, have _______ overlapping plates surrounded by a fleshy mantle. They usually eat _____________. Bivalves (Pelecypoda) are usually filter feeders. They use their _________ to filter and sort food as well as get O_2. Many dig with their ________. The largest class of Mollusca is Class ____________________. The shell may be flattened such as a ___________ and the delectable ___________ or coiled, like turban snails and dogwinkles. It may be weird shaped like cowries or like _______________ which resembles a worm tube. (Use your field guide and don’t confuse tube worms and snails!). The ____________ don’t have shells at all but are Gastropods. The most advanced invertebrate brain and eyes are found in the mollusc class ___________________ which includes the shell-less ______________ and the squid with its thin internal reduced shell called a ________________________.

The huge & diverse phylum _________________________includes insects and spiders on land. Most marine members of this phylum belong to the subphylum ______________________ and have _____ pairs of antennae. Cirripedia, the barnacles, filter feed use feathery legs called ____________. The final larval stage which later settles to become the sessile adult is the _____________________________.

Another subclass, the abundant ___________________, are generally planktonic. They swim using their two long _______________ and have a single light sensitive _________ (like a Cyclops!). An order with completely segmented bodies, the __________________ have all similar legs. and are _____________________ flattened. An example is ___________________. Another completely segmented order, the _______________ included beach hoppers. They are laterally flattened and have specialized leg types. The most familiar order, which includes the crabs, shrimp & lobster, is the _________________. They have stalked eyes. The anterior shell segments covering the head and thorax are fused to form the _________________. The ________________ is segmented and may extend outward as in shrimp or be folded under as in Brachyuran or true ____________. _____________ crabs generally live in the shells of dead gastropods and have soft coiled _____________. The sand or __________ crab digs into the sand and filter feeds using its ___________________.

The phylum ____________________ means spiny skin. The sea stars belong to the Class _____________________. The opening to the water vascular system on the aboral side is called the __________________. The system terminates in many _____________________ which act like suction cups. Brittle stars, of the Class ___________________ have long sinuous rays which easily break off therefore they don’t contain _________________. Sea urchins & sand dollars belong to the class ____________________. They have a solid internal skeleton called a _____________ and spines which pivot on knobs. Like sea stars, urchins have ______________________ for gripping and ________________________ for cleaning and defense. The class _________________________ includes the squishy, tough sea cucumber. They feed using tentacles that are modified oral _________________________.

Tunicates, including sea squirts, are members of our own phylum, ______________ whose larvae look like tadpoles. The distinctive textured tunic contains the skeletal material _____________________, more typical of plants than animals. Food is filtered by gill slit openings in the ____________________. Some colonial tunicates such as __________________ may share their tunic and excurrent __________________.