Ap Biology Chapter 33 Vocabulary

Front 1

alimentary canal

Back 1

A digestive tract consisting of a tube running between a mouth and an anus.

Front 2

ammonite

Back 2

A shelled cephalopod that was the dominant invertebrate predator for millions of years until the end of the Cretaceous period.

Front 3

amoebocyte

Back 3

An amoeba-like cell that moves by pseudopodia, found in most animals; depending on the species, may digest and distribute food, dispose of wastes, form skeletal fibers, fight infections, and change into other cell types.

Front 4

arthropod

Back 4

A segmented coelomate with a chitinous exoskeleton, jointed appendages, and a body formed of distinct groups of segments.

Front 5

book lung

Back 5

An organ of gas exchange in spiders, consisting of stacked plates contained in an internal chamber.

Front 6

brachiopod

Back 6

A marine lophophorate with a shell divided into dorsal and ventral halves. Brachiopods are also called lamp shells.

Front 7

chelicera

Back 7

One of a pair of clawlike feeding appendages characteristic of cheliceriforms.

Front 8

cheliceriform

Back 8

An arthropod that has chelicera, and a body divided into a cephalothorax and an abdomen. Living cheliceriforms include sea spiders, horseshoe crabs, scorpions, ticks, and spiders.

Front 9

choanocyte

Back 9

A flagellated feeding cell found in sponges. Also called a collar cell, it has a collar-like ring that traps food particles around the base of its flagellum.

Front 10

closed circulatory system

Back 10

A circulatory system in which blood is confined to vessels and is kept separate from the interstitial fluid.

Front 11

cnidocyte

Back 11

A specialized cell for which the phylum Cnidaria is named; contains a capsule containing a fine coiled thread, which, when discharged, functions in defense and prey capture.

Front 12

complete metamorphosis

Back 12

The transformation of a larva into an adult that looks very different, and often functions very differently in its environment, than the larva.

Front 13

copepod

Back 13

Any of a group of small crustaceans that are important members of marine and freshwater plankton communities.

Front 14

crustacean

Back 14

A member of a subphylum of arthropods that includes lobsters, crayfish, crabs, shrimps, and barnacles.

Front 15

cuticle

Back 15

(1) A waxy covering on the surface of stems and leaves that acts as an adaptation to prevent desiccation in terrestrial plants. (2) The exoskeleton of an arthropod, consisting of layers of protein and chitin that are variously modified for different functions. (3) A tough coat that covers the body of a nematode.

Front 16

decapod

Back 16

A member of the group of crustaceans that includes lobsters, crayfish, crabs, and shrimp.

Front 17

echinoderm

Back 17

A slow-moving or sessile marine deuterostome with a water vascular system and, in adults, radial anatomy. Echinoderms include sea stars, brittle stars, sea urchins, feather stars, and sea cucumbers.

Front 18

ectoproct

Back 18

A sessile, colonial lophophorate commonly called a bryozoan.

Front 19

eurypterid

Back 19

An extinct carnivorous cheliceriform also called a water scorpion.

Front 20

exoskeleton

Back 20

A hard encasement on the surface of an animal, such as the shell of a mollusc or the cuticle of an arthropod, that provides protection and points of attachment for muscles.

Front 21

foot

Back 21

(1) The portion of a bryophyte sporophyte that gathers sugars, amino acids, water, and minerals from the parent gametophyte via transfer cells. (2) One of the three main parts of a mollusc; a muscular structure usually used for movement.

Front 22

gastrovascular cavity

Back 22

An extensive pouch that serves as the site of extracellular digestion and a passageway to disperse materials throughout most of an animal’s body.

Front 23

hermaphrodite

Back 23

An individual that functions as both male and female in sexual reproduction by producing both sperm and eggs.

Front 24

hexopod

Back 24

An insect or closely related wingless arthropod.

Front 25

incomplete metamorphosis

Back 25

A type of development in certain insects, such as grasshoppers, in which the young (called nymphs) resemble adults but are smaller and have different body proportions. The nymph goes through a series of molts, each time looking more like an adult, until it reaches full size.

Front 26

invertebrate

Back 26

An animal without a backbone. Invertebrates make up 95% of animal species.

Front 27

isopod

Back 27

A member of one of the largest groups of crustaceans, which includes terrestrial, freshwater, and marine species. Among the terrestrial isopods are the pill bugs, or wood lice.

Front 28

mandible

Back 28

One of a pair of jaw-like feeding appendages found in myriapods, hexapods, and crustaceans.

Front 29

mantle

Back 29

A fold of tissue in molluscs that drapes over the visceral mass and may secrete a shell.

Front 30

mantle cavity

Back 30

A water-filled chamber that houses the gills, anus, and excretory pores of a mollusc.

Front 31

medusa

Back 31

The floating, flattened, mouth-down version of the cnidarian body plan. The alternate form is the polyp.

Front 32

mesohyl

Back 32

A gelatinous region between the two layers of cells of a sponge.

Front 33

molting

Back 33

A process in arthropods in which the exoskeleton is shed at intervals, allowing growth by the production of a larger exoskeleton.

Front 34

myriapod

Back 34

A terrestrial arthropod with many body segments and one or two pairs of legs per segment. Millipedes and centipedes comprise the two classes of living myriapods.

Front 35

nematocyst

Back 35

A stinging, capsule-like organelle in a cnidocyte.

Front 36

open circulatory system

Back 36

A circulatory system in which fluid called hemolymph bathes the tissues and organs directly and there is no distinction between the circulating fluid and the interstitial fluid.

Front 37

osculum

Back 37

A large opening in a sponge that connects the spongocoel to the environment.

Front 38

parthenogenesis

Back 38

A type of reproduction in which females produce offspring from unfertilized eggs.

Front 39

phoronids

Back 39

A tube-dwelling marine lophophorate.

Front 40

planarian

Back 40

A free-living flatworm found in unpolluted ponds and streams.

Front 41

polyp

Back 41

The sessile variant of the cnidarian body plan. The alternate form is the medusa.

Front 42

radula

Back 42

A straplike rasping organ used by many molluscs during feeding.

Front 43

spongocoel

Back 43

The central cavity of a sponge.

Front 44

suspension-feeder

Back 44

An aquatic animal, such as a clam or a baleen whale, that sifts small food particles from the water.

Front 45

torsion

Back 45

A characteristic of gastropods in which the body rotates during development.

Front 46

trilobite

Back 46

An extinct arthropod with pronounced segmentation and appendages that varied little from segment to segment.

Front 47

trochophore larva

Back 47

Distinctive larval stage observed in annelids and molluscs.

Front 48

tube foot

Back 48

One of numerous extensions of an echinoderm’s water vascular system. Tube feet function in locomotion, feeding, and gas exchange.

Front 49

visceral mass

Back 49

One of the three main parts of a mollusc, containing most of the internal organs.

Front 50

water vascular system

Back 50

A network of hydraulic canals unique to echinoderms that branches into extensions called tube feet, which function in locomotion, feeding, and gas exchange.