Phylum Cnidaria

gastric pouches

4 connect with the stomach in scyphozoans and a complex system of radial canals that branch to the ring canal, completing the GVC

cnidocil

A trigger-like object at the edge of a cnidocyte. It basically harpoons the prey..

rhopalium

A unit containing statocysts for balance, ocelli for light sensitivity, and simple eyes with lenses in certain jellyfish.

gastrovascular cavity

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

siphonoglyph

Ciliated groove in pharynx, directs water into GV cavity, allowing for diffusion to begin.

extracellular digestion

Digestion that takes place outside of the cell.

ephyrae

It is a miniature medusa produced by asexual bedding of a scyphistoma, mature into sexual medusae

biradial symmetry

Portions of the body are specialized and only two planes of sectioning can divide the animal into perfectly similar halves

Class Staurozoa

Solitary polyps only. medusa absent. polyp surface extended into eight clusters of tentacles surrounding mouth; attachment via adhesive disc; all marine

Ceriantipatharia

Sub class Anthozoa. Thorny corals: Unpaired septa, hexamerous, deep sea, branched.

Zoantharia

Subclass Anthozoa. Sea anemones and hard corals. Hexamerous, paired septa, simple tentacles. Contains orders actinaria(lacks exoskeleton, solitary) and scleractinia(colonial, CaCo exoskeleton)

hydrostatic skeleton

Support structure that consists of water contained under pressure in a closed cavity.

hexamerous

Symmetry based on 6's as seen in subclass Zoantharia

acontia

Thread-like extentions of septa in GV cavity. Possess nematocysts. Protrudes through mouth and body wall. Helps in food capture and defense? Can have a mutual symbiosis.

glutathione

What triggers the harpoon of a stinging cell?

hypostome

a conical elevation where the mouth is, encircled by 6 to 8 hollow tentacles, can extend when animal is hungry

velum

a membrane on the subumbrellar surface of jellyfishes of class hydrozoa

pedal disc

a structure at the aboral end of a polyp used for attachment

hydrocorals

aka "pseudocorals" not corals at all; colonial hydrozoans (like portuguese man-o-war) that secrete CaCo3

budding

asexual reproduction in which a part of the parent organism pinches off and forms a new organism

gonangia

bud on polyp that produces a medusa bud

cnidae

capsule-like organelles that are capable of everting (turning inside out) and that give phlyum Cnidaria its name

tissue

cnidaria level of organization

cnidoblast

cnidocyte

ctenes

comb plates

polyps

cylindrial forms that adhere to the substrate by the aboral end of the body

gastrodermis

endodermal, consists chiefly of large, ciliated columnar epithelial cells, include nutritive muscular, interstitial and gland cells

ectodermal

epidermis

ocelli

eyespots; simple organs that detect light; important for survival of symbiotic cnidarians

hydranths

feeding polyps-feed whole colony

pedalium

flattened, tough blade from which tentacles extend

epitheliomuscular cells

form most of the epidermis and serve both for contraction and for muscular contraction. Bases of these are myofibrils, which when contracted shorten the body or tentacles.

fission

form of asexual reproduction in which an organism splits into two, and each half grows new parts to become a complete organism

solenia

gastrodermal tubes through which polyps in colonies communicate

medusae

have a bell shaped or unbrella shaped body; the layer of mesoglea is very thick and constitutes most of their bulk

diploblastic

having 2 germ layers: ectoderm and endoderm.

mesoglea

in cnidarians, the jellylike material located between the ectoderm and the endoderm

Class Hydrozoa

includes animals which spend part of their lives in both the medusa and polyp form; hydra is the exception and spends its entire life as a polyp

Class Cubozoa

includes box jellies and sea wasps, the medusa is box shaped and has complex eyes, often have highly toxic cnidocytes

operculum

lid covering cnidae

nerve net

nervous responses in cnidarians are controlled by a diffuse web of interconnected nerve cells

Class Anthozoa

no alternation of generations the medusoid phase being entirely suppressed: sea anemones, corals

dactylozoids

polyps designed for colony defense

strobila

scyphistoma becomes this which begin to bud off young medusa

colloblasts

secrete a sticky substance that binds to their prey

neuromuscular system

sensory cell and nerve net combination

velarium

shelflike exension of the sumubrellar edge in cubazoans

statocysts

simple organs that detect gravity, enabling cnidarians to stay upright

octocorallian corals

soft corals, sea pansies,and sea fans and other gorgonian corals, strict octomerous symmetry

cnidocytes

stinging cells located along the tentacles of cnidarians; used for defense and to capture prey

nematocysts

stinging organelles

zoantharian corals

stony (true) corals, miniature sea anemones that live in calcareous cups they secreated

Octocorallia

subclass of Anthozoa comprising ~3,000 species of water-based organisms formed of colonial polyps with 8-fold symmetry. It includes the blue coral, soft corals, sea pens, and gorgonians; NOT STONY CORALS

planula

the free-swimming, ciliated larva of a cnidarian

manubrium

the portion projecting from the oral side of a jelly fish medusa bearing the mouth, oral cone, presternum or anterior part of sternum

polymorpism

the presence in a species of more than one structural type of individual

oral disc

the region of a cnidarian's body with the mouth and manubrium at its center, and a whorl of tentacles at its margin

Class Scyphozoa

they spend most if not all their lives as medusae

comb plates

usually possessed by ctenophora and are used for locomotion. (have eight pairs)

strobilation

when scyphozoen form medusae (polyps rip off)

scyphistoma

when the planula larva escapes from the parent and attaches to a substratum, it develops into tiny polyps called this