| A | B |
|---|
| earthworm | swallows soil |
| The earthworm enriches soil | with its castings. |
| castings | the soil that has passed through the earthworm's body |
| The earthworm helps keep the soil light and loose | so that rain can soak water down to water the roots of plants. |
| setae | movable bristles |
| parasitic worms | leeches, tapeworms, and roundworms |
| leech | fastens itself to the skin of its host and feeds on the host's blood |
| tapeworm | grows inside the intestines of a host, robbing it of important nutrients |
| roundworms | can live in the lymph nodes, intestines, and even the muscles of their hosts, taking their nourishment from the host's blood or partially digested food |
| mollusks make themselves | beautiful, hard coverings called shells |
| mollusk's shell | made of calcium carbonate |
| mantel | the tissue that produces the shell |
| gastropod | stomach-foot |
| snail | the farmer's enemy because it eats young plants |
| univalves | one-shelled molllusks |
| cowrie | smooth, glassy shell |
| conch | ridged, bumpy shell |
| slug | doesn't have a protective shell |
| slugs move | by expanding and contracting its foot |
| sea slug | nudibranch |
| bivalves | mussels, oysters, clams, and scallops |
| bivalves have | two shells |
| earthworms | are beneficial to farmers |
| When a bivalve is attacked | its strong muscles close its shell. |
| cephalopod | head-foot |
| The cephaopod has | two eyes and several tentacles |
| The cephalopod uses tentacles to | catch fish and other prey |
| Cephalopods swim by | sucking water into a chamber in their bodies and then forcing the water out. |
| jet propulsion | a type of movement in which a mollusk sucks water into a chamber of its body and then rapidly forces water out |
| octopus | cephalopod with eight long tentacles, each with two rows of muscles that act like suction cups |
| An octopus has excellent | vision |
| An octopus protects itself by | shooting a dark, inky substance in to the water and swimming away |
| squid and cuttlefish have | ten tentacles |
| nautilus | has a beautifully designed external shell that protects its body |
| nautilus has | 94 tentacles with no suction cups |
| When a nautilus is in danger | it locks itself inside its shell |
| sea star | starfish |
| The starfish does not look like a | plant, animal, or rock |
| The starfish has | five rays |
| rays | arms |
| tube feet | the feet of sea stars and sea urchins that act like suction cups and help the sea star keep a firm grip on its prey |
| How does the sea star eat? | it will force its tonguelike stomach into the opening and begin to digest its prey |
| relative of the sea star that is covered with spines | sea urchin |
| How does a sea urchin protect itself? | It uses its spines |
| sand dollars | flat sea urchins |
| 3 other relatives of the sea star | sea lily, feather star, sea cucumber |
| sponge | has a number of small openings in the sides of its body |
| pores | small openings |
| flagella | small hairlike-structures |
| What do flagella do? | keep water moving through the body and collect any microscopic food particles carried by the water |
| sea anemone | the flowerlike invertebrate found on the ocean floor which uses its colorful tentacles to paralyze its prey |
| coral polyp | builds a limestone cup at the base of its tubelike body |
| The polyp captures prey | by stinging tentacles |
| Where do most coral polyps live? | in colonies |
| Coral polyps build | coral reefs |
| hydra | tiny freshwater invertebrate with tentacles around its mouth |
| jellyfish | beautiful, bowl-shaped animal that floats near the surface of the water trailing stinging tentacles |
| A jellyfish's tentacles have | stinging cells |
| jellyfish life stages | larva, young polyp, polyp, polyp-producing medusa, young medusa, adult jellyfish |
| medusa | free-floating, unbrella-shaped stage of a jellyfish |
| Portuguese man-of-war | a colony of several jellyfishlike creatures living and working together |
| protozoans | the smallest possible animals; made up of one single cell that performs all tasks ordinarily shared by 1000's of cells |
| cell | smallest living unit in any living organism |
| three main parts of a cell | cell membrane, cytoplasm, and the nucleus |
| cell membrane | surrounds the cell and protects it |
| cytoplasm | a jellylike fluid that fills the cell |
| organelles | a tiny organ in a cell |
| nucleus | located in the center of the cell; directs the work of the cell |
| choromosomes | contain the instructions for running the cells and making needed parts |
| chromosomes determine | the characteristics of the organism as a whole |
| amoeba | has no definite shape because is shape changes continually as it moves |
| pseudopods | false feet |
| cilia | tiny hairlike structures that help a paramecium move |
| food vacuole | a tiny storage container |
| paramecium | common protozoan that looks like a shoe or a slipper |
| Anton van Leeuwenhoek | first person to observe protozoans and write down what he saw |
