| A | B |
|---|
| What group of organisms are the 1st to have a true coelom? | mollusks & annelids |
| 1st stage of larval development in mollusks & annelids | trochophore |
| 5 characteristics of mollusks | true coelom, 3 main body parts, organ systems, bilateral symmetry, most have 1 or more shells |
| What are the 3 main body parts of mollusks | head, foot, visceral mass |
| A muscular organ used for movement | foot |
| structure containing mouth, sense organs, & ganglia | head |
| What does the word viscera refer to | organs |
| Structure that contains the heart & organs for digestion, excretion & reproduction | visceral mass |
| An epidermal layer that covers the visceral mass & makes the shell | mantle |
| what is an advantage of a shell | protection |
| What is a disadvantage of a shell | reduces the area for exchange of gases |
| organs specialized for gas exchange with water | gills |
| What phylum are clams, oysters, octopus, and snails in | Mollusca |
| What are the 4 classes of Mollusca? | Polyplacophora, Gastropoda, Bivalvia, Cephalopoda |
| What does univalve mean? | 1 shell |
| Seashore organisms that have a shell made of 8 overlapping plates | chitons |
| what is the largest & most diverse class of Mollusca | Gastropoda |
| What kind of a circulatory system do snails have? | open |
| What do aquatic snails use to breathe with? | gills |
| What do land snails use to breathe? | mantle cavity acts as a modified lung |
| What is the term for a blood cavity? | hemocoel |
| Type of circulatory system in which blood does not flow in vessels | open |
| What does Gastropod mean? | stomach-foot |
| What organisms are in the class Gastropoda? | snails &slugs |
| A flexible tongue like structuree covered with teeth | radula |
| What kind of snails are hermaphrodites? | land snails |
| what kind of snails have separate sexes? | aquatic snails |
| How fast do snails move? | 3 m/hr |
| Where are a snail's eyes? | On its tentacles |
| How are snails & slugs different? | slugs have no shell |
| How do slugs breathe? | through the lining of the mantle cavity |
| What class are the clams, oysters, & scallops in? | Bivalvia |
| What structure do bivalves use to dig themselves into the sand? | foot |
| Do bivalves have a distinct head region? | no, but they have ganglia in the anterior end |
| Describe the outer layer of a shell of a bivalve & its function | thin - protects from acid in the water |
| Describe the middle layer of the shell of bivalve & its function | thick, made of calcium carbonate and strengthens the shell |
| describe the inner layer of the shell of a bivalve & its function | smooth & shiny, made of mother of pearl, protects soft body |
| what 2 muscles close the shell of bivalves? | adductor muscles |
| structure of bivalve in which cilia bring in water & food over the gills | incurrent siphon |
| structure in which water exits the bivalve | excurrent siphon |
| Where are the sense cells in a bivalve | on the edge of the mantle - respond to touch |
| where are the ganglia of a bivalve | above mouth, in digestive system, & in the foot |
| Bivalve that is permanently attached to a hard suface | oyster |
| Bivalve that moves thru the water by opening & shutting their shell - scoot by 'jet propulsion' | scallops |
| What class are octopus & squid in? | Cephalopoda |
| What does Cephalopod mean? | 'head-foot' |
| the term for the sharp beak of a Cephalopod | radula |
| Where do squid live? | oceans |
| What is the largest invertebrate | giant squid- can be about 20m long |
| How many tentacles does a squid have? | 10 |
| How many tentacles does an octopus have? | 8 |
| How do squids protect themselves? | by squirting an inky substance or by using chromatophores to blend in |
| What is the only cephalopod that has kept its shell? | chambered Nautilus |
| What does the word Annelida mean? | 'little rings' |
| What is the phenomenon of having a segmented body called? | metamerism |
| What are the body sections of Annelids called? | metameric units |
| What are the 3 classes of the Phylum Annelida? | Oligochaeta, Polychaeta, Hirudinea |
| What does the word Oligochaeta mean? | 'few hairs' |
| What does the word Polychaeta mean? | 'many hairs' |
| Tubes that eliminate nitrogen waste in Annelids? | nephridia |
| What class are earthworms in? | Oligochaeta |
| What class are featherduster and bristleworms in? | Polychaeta |
| What class are leeches in? | Hirudinea |
| Do earthworms have parapodia? | no |
| What are the 2 sets of muscles that earthworms have? | circular & longitudinal |
| Which muscles of the earthworm make the worm thinner? | circular |
| which muscles of the earthworm wrinkles them up | longitudinal |
| What are the external bristles of the earthworms called? | setae |
| What do earthworms feed on? | soil & organic matter |
| What is the undigested matter, dirt & feces of the earthworm called | castings |
| Where is the food temporarily stored in the earthworm? | crop |
| What organ grinds up the food in an earthworm | gizzard |
| What kind of a circulatory system do earthworms have? | closed |
| What kind of a circulatory system do cephalopods have? | closed |
| What type of circulatory system is more efficient? | closed |
| What are the 2 main vessels that transport blood in earthworms? | the ventral & dorsal vessel |
| what vessel transports blood from anterior to posterior | ventral |
| What vessel transports blood from posterior to anterior? | dorsal |
| What connect the 2 main vessels of the earthworm | aortic arches |
| How many pairs of aortic arches are there in the earthworm? | 5 |
| what do earthworms use to breathe? | they have no respiratory organs - breathe thru moist skin |
| What do earthworms use to sense direction? | light receptors in head & tail |
| Do earthworms have separate sexes or are the hermaphrodites? | hermaphrodites - but can't fertilize themselves |
| What is the swelling around the sex organs of an earthworm called? | clitellum |
| What are the fleshy unjointed paddle like appendages of the polychaetes called? | parapodia |
| What do polychaetes use their parapodia for? | walking, swimming or digging |
| What class are the leeches in? | Hirudinea |
| What is the smallest class of Annelida? | Hirudinea |
| What class of Annelida is parasitic | Hirudinea |
| Where do you find leeches? | fresh calm bodies of water |
| What were leeches used for in medieval times? | curing illness |
| What are leeches used for today in medicine | prevents scabs from forming allowing wounds to heal from the inside out |
