| A | B |
|---|
| abdomen | hindmost of the three main body divisions of an insect; posterior section of the arthropod body |
| aboreal | tending to live in trees |
| ampulla | a pore or dilated portion of a duct found in certain calcareous hydrozoans that produce medusae from internal self-fertilization |
| anterior | Towards the head |
| appendage | extremity: an external body part that projects from the body |
| beak | The rounded or pointed extremity of a bivalve shell; Upper portion of the mandible (mouth) |
| cephalization | formation of a distinct head region ? ie localization of sensory organs, mouth and brain ganglia in the anterior region of the animal. This is seen to a small degree in nematode, but to a much larger degree in annelids, arthropods and chordates |
| chiliped | in body of a decapod crustacean, 1st pereiopod (one of the five walking limbs); claw used in defense and capturing food |
| choanocytes | flagellated cells in sponges having a collar of cytoplasm around the flagellum (collar cells); they maintain a flow of water through the body |
| clitellum | swollen band-like gland on a segmented worm (annelid) that releases fluid for building a cocoon for the eggs |
| crop | thin-walled expanded portion of the alimentary tract used for the storage of food prior to digestion that is found in many animals, including earthworms, leeches, insects, and birds |
| dorsal | towards the back of the body |
| ectoderm | germ layer; covers surface of emryo; becomes outer covering/skin, gives rise to nervous sytem (some animals) |
| endoderm | germ layer; innermost; becomes lining of digestive tract and some organs |
| external fertilization | eggs deposited in watery environment, sperm deposited nearby into water and swim to egg (most fish and amphibians) |
| eye spot | in planaria, simple eye-cup without lens; differentiates the direction and the intensity of light |
| filter feeder | Organism (clam, mussel, oyster) that feeds by pumping large volumes of water to consume material in suspension, such as phytoplankton |
| flame cell | organ of excretion in flatworms |
| free living | non-parasitic roundworm |
| gill | In aquatic organisms, gills are a respiratory organ for the extraction of oxygen from water and for the excretion of carbon dioxide |
| gizzard | muscular stomach that is found in birds, earthworms, and other animals |
| hermaphrodite | organism that has both male and female reproductive organs |
| hookworms | parasitic bloodsucking roundworms having hooked mouth parts to fasten to the intestinal wall of human and other hosts |
| hydrostatic skeleton | body's shape and/or function is maintained by an incompressible fluid such as blood or hemolymph; primarily found in soft-bodied invertebrates such as such as earthworms and jellyfish |
| internal fertilization | male deposits sperm within the female's body (reptiles, birds, and mammals) |
| madreporite | small porose button on upper surface of the body ring of starfish, through which the water vascular system connects with the exterior |
| mesoderm | germ layer; between eno and ectoerm; becomes muscle and most organs (circulatory and excretory) |
| morula | The fertilized egg after a few days of development when it forms a ball of 16 cells |
| nephridium | invertebrate organs which function similarly to kidneys |
| nerve net | type of simple nervous system found in members of the phylum cnidaria; consists of interconnected neurons lacking a brain; allows cnidaria to sense touch and pain, and to detect food and other chemicals |
| oral | Pertaining to the mouth |
| osculum | large hole at the top of a sponge that expels water and wastes |
| ostia | Surface pores on a sponge |
| parasitic | roundworms or other organisms feeding off other organisms |
| pedicellaria | in starfish (echinoderm), pincer-like structures located among the bases of the spines that cover the arms and central disk; appear to protect the starfish from small animals or larvae that might settle on the body surface |
| pinworms | roundworm parasite |
| posterior | towards the tail |
| proglottid | tapeworm segment having both male and female reproductive organs |
| regeneration | ability to re-grow body parts that are lost or damaged |
| scolex | head and most distinctive part of adult tapeworm |
| seta | Bristle-like protrusion at the tip of nematodes; tactile sensory organs usually located around the oral openings |
| siphon | In molluscs, a tube-like extension of the mantle edge to conduct water current for respiration and/or feeding and for some bivalves, locomotion |
| spongocoel | Central body cavity of sponges |
| swimmeret | one of the paired abdominal appendages of certain aquatic crustaceans that are used for carrying the eggs in females, swimming, and respiration |
| symmetry | correspondence in size, shape and relative position of parts on opposite sides of a dividing line or median plane |
| trichinosis | disease caused by round-worm trichinella spiralis; caused by eating undercooked pork |
| ventral | towards the belly |
| zygote | diploid cell formed when haploid sperm nucleus fuses with haploid egg nucleus |
