Phylum Porifera

• Image from: Sponges
• Common Names: sponges (encrusting, tubular, pectin, boring)
• No symmetry
• Two layers of cells
• Sessile (don’t move)
• Filter feeders
• Major food source for other organisms (especially nutibranchs and sea turtles)
• Some have spicules (glass like structures) that can serve for support or defense
• for more info see: Porifera - life history and ecology

Phylum Cnidaria (Coelenterata)

• Image from: Cnidaria
• Common Names: sea anemone, hydra, coral, jelly fish
• Typically radial symmetry
• Eat with mouths and digest with stomachs
• Basic nervous system
• Most have specialized stinging cells called newmatocysts for defence
• Most have both a medusa (arms hanging down) and polyp (arms up) life stage
• Most are carnivorous, some have symbiotic relationships with photosynthetic algae
• for more info see: Major Groups of Cnidaria

Phylum Ctenophora

• Image from: Ctenophore
• Common Name: Comb Jellies
• No shells or hard surfaces
• Eight rows of cilia combs to help them swim
• Video: sea gooseberry swimming
• Many are deep water species and bioluminescent
• for more info see: Ctenophora

Phylum Annelida

• Image from: Annelids
• Lots of species, many are important food sources
• Segmented worms, normally with legs attached to each segment
• Most dig, burrow, or build tubes for protection
• Most are filter feeders
• for more info see: Annelida

Phylum Mollusca, Class Bivalvia

• Image from: Bivalves
• Common Names: Clams, oysters, scallops, mussels
• Have a foot, a siphon, and two shells
• Susceptible to PSP (paralytic shellfish poisoning)
• Important commercial market for farming
• video: giant clams (the heaviest molluska)

Phylum Mollusca, Class Gastropoda

• Image from: Gastropods
• Common Names: Snails, sea slugs, nutibranchs, abalone
• One shell or no shell
• Feed with a radula, may have external gills, have a large flat foot for movement

Phylum Mollusca, Class Cephalopoda

• Picture from: Mollusca
• Common Names: Octopus, squid, nautilus
• Have a siphon (used as a jet to swim), and suckers (which can smell, taste, and feel)
• Important prey and predator
• Skin has special cells - chromatophors which allow them to chance color
• Marinebio.org - Squid and Octupi
• Video: Common cuttlefish attacking a crab

Phylum Arthropoda,  Class Maxillopa

• Image from: Copepods
• Common Names: Copepods, barnacles, mystacocarids, tantulocarids, branchiurans, andostracods
• Most species are small
• Most feed by means of their maxillae (rather than filter feeding using thoracic appendages to move water) Barnacles feed with thoracic appendages, but in a way that is unique among crustaceans
• A basic plan of 5 head and 10 trunk segments (6 thoracic and usually 4 abdominal), followed by a terminal telson

Phylum Arthropoda Class Malacostracoda

• Image from: Arthropods
• Common Names: crabs, lobsters, shrimp, prawns, crayfish
• Exhibit the hard, calcified exoskeleton typical of crustaceans
• In order to grow they must shed their exoskeleton in a process called moulting. When they first emerge with a new shell they are much easier to eat (in a restaurant you may order softshell crab) and vulnerable to attack.
• The body is divided into sections (head, thorax, and abdomen)
• All malacostracans possess five segments in the head, eight in the thorax, and six in the abdomen

Phylum Echinodermata

• Image from: Echinoderms
• Common Names: sea stars, sea urchins, brittle stars, and sea cucumbers
• Use tube feet to move
• Internal circulatory system
• Water vascular system (most complex among invertebrates), connected to (source of power for) tube feet

1. Sponges are considered to be the most primative of animals.  What do the body shapes of sponges lack that all other animals posess.
2. Go to Monterey Bay Aquarium - Online Field Guide, click on invertebrates.  Identify one example (one species) of each of the phylum in your notes.
3. Within the online field guide, click on any member of phylum Mollusca, class Gastropoda (think abalone, snails, chitins, or limpets.  Describe what a radula is and how these organisms use a radula to feed.
4. Watch "There is no such thing as a Jelly Fish." Describe three surprising things you learn.
5. Giant clams are the largest mollusk (by weight).  How did they get so big?  Click on the video link, watch the video then click "biology" to the left.  Describe the symbiotic relationship of the algae that live within the clams.  How does the relationship help both species?  
6. Explain how sea anemones battle one another for control of intertidal communities.
7. Click on the attached file, Bivalves of Alaska.  Open up this PDF document.  Describe what PSP is, which species your most likely to find it in, and which months of the year its most common.
8. Horseshoe crabs are not really crabs at all (that is not malacostracoda.)  They are members of an ancient sub-phylum Chelicerata.  Click on the link, watch the video, and then click on biology. Describe what you learn about their ecological importance.
   
9. Copy the table below into your page of questions.  Use your textbook (Chapter 7) and the notes above to fill in the blanks.

Phylum	Common Names	Distinguishing Features	Symmetry	Respitory Exchange	Circulatory System
			Asymmetrical
		Newmatocysts
	snails, clams, octopi	a foot or cyphon			open or closed
		jointed legs		Gills
Echinodermata

10. In the table below, match the name of the larvae to the name of the adult arthropod.