Phylum Cnidaria

epitheliomuscular cells

-Cnidarian muscle that form longitudinal muscle layers along body surface.

hydrostatic skeleton

A fluid skeleton in many soft-bodied invertebrates, including annelids, that allows an organism to change shape but not volume.

medusa

A free-swimming cnidarian with a bell-shaped body and tentacles

cnidocil

A hairlike trigger on the cnidocyte surface

tentacle

A long, slender, flexible arm-like structure found around the mouth or head of an animal.

septa/mesenteries

A mesentery is a membrane inside the body cavity of an animal. septa being a partition separating two chambers, such as that between the nostrils or the chambers of the heart.

sclerites

A plate on the body wall surrounded by membrane or sutures.

endocytosis

A process in which a cell engulfs extracellular material through an inward folding of its plasma membrane.

mutualism

A relationship between two species in which both species benefit

asexual reproduction

A reproductive process that involves only one parent and produces offspring that are identical to the parent.

sexual reproduction

A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents

mechanoreceptor

A sensory receptor that responds to mechanical disturbances, such as shape changes (being squashed, bent, pulled, etc.). Mechanoreceptors include touch receptors in the skin, hair cells, in the ear, muscle spindles, and others.

fission

A splitting apart

reef

A submerged ridge of rock or coral near the surface of the water.

zooxanthellae

Algae that lives symbiotically with reef-building coral species . They use waste products from the coral to photosynthesize and in return, coral gets energy, and is able to build calcium carbonate reefs faster

alternation of generation

Alternating sexual and asexual generation reproduction

brood pouch

Area of female's belly that is unfeathered. It becomes highly vascularized during egg incubation to increase heat transfer

explain how coral reefs are built

Coral Reefs - Formed from millions of tiny tube-shaped polyps, an animal life form encased in tough limestone skeletons - they anchor to a rocky surface, eat plankton and minuscule shellfish (caught with poisonous tentacles near the mouth), use calcium carbonate absorbed from chemicals given off by algae to harden their body armor and cement themselves together (form shapes of many colors), reproduce through eggs and larvae; reef grows by branching out shoots of polyp

gastrovascular cavity

Digestive chamber with a single opening, in which cnidarians, flatworms, and echinoderms digest food

explain why corals are considered bio-indicators

Disturbances of coral reefs are caused by a complex combination of stressors including those arising from climate change, diseases, predation, destructive fishing practices, storms and changes in water quality.

dioecious

Having male and female reproductive organs in separate plants or animals

explain the ecological and economic importance of coral reefs

Healthy coral reefs support commercial and subsistence fisheries as well as jobs and businesses through tourism and recreation. able to support the many creatures that inhabit them

class hydrozoa

Hydras, most live as colonies. Within the colony they are specialized for specific functions (feeding, moving, and hunting). Portuguese Man-O-War: marine hydrozoa. Hydra: Freshwater hydrozoa: lack a medusa stage.

class alcyonacea (soft corals)

Hydrozoa have calcified skeletons of aragonite and calcite and a good fossil record, whereas the long fossil record of the class Scyphozoa (jelly fish) is comprised mostly of molds and casts.

explain how a colony of hydrozoan polyps is different from a colony of scleractinian polyps

Hydrozoa have calcified skeletons of aragonite and calcite and a good fossil record, whereas the long fossil record of the class Scyphozoa (jelly fish) is comprised mostly of molds and casts.

diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

coral bleaching

Occurs when a coral becomes stressed and expels most of its colorful algae, leaving an underlying ghostly white skeleton of calcium carbonate

internal fertilization

Process in which eggs are fertilized inside the female's body

explain why stony corals are rarely seen in cooler, nutrient rich waters

Reefs that rose too slowly could become drowned reefs. They are covered by so much water that there was insufficient light.

rhophalium

Rhopalia (singular: rhopalium) are small sensory structures of Scyphozoa (typical jellyfish) and Cubozoa (box jellies). In Aurelia they lie in marginal indententions around the bell and are flanked by rhopalial lappets.

order scleractinia (stony corals)

Scleractinian ("hard-rayed") corals first appeared in the Middle Triassic and refilled the ecological niche once held by tabulate and rugose corals. They are probably not closely related to the extinct tabulate or rugose corals, and probably arose independently from a sea anemone-like ancestor. Their pattern of septa differs markedly from that of the Rugosa, being basically six-rayed. For this reason, scleractinians are sometimes referred to as hexacorals.

oral disk

The broad disk on which the tentacles attach in a anemone.

corallite

The cup-shaped calcium skeleton in which a coral polyp sits

external fertilization

The process by which the female lays eggs and the male fertilizes them once they are outside of the female

ephyra

Tiny medusae that comes off the polyps in sexual reproduction

nerve ring

a circle of nerves that surrounds the mouth

polyp

a typical coelenterate individual with a hollow tubular body whose outer ectoderm is separated from its inner ectoderm by mesoglea

explain what alternation of generations means and apply it to cnidarian reproduction

alternation of generation is a shift between asexual and sexual reproduction in different generations

chemoreceptor

chemical sensors in the brain and blood vessels that identify changing levels of oxygen and carbon dioxide

compare the body plans of cnidarians

cnidarian have the polyp and medusa body plans. a polyp is shaped like a vase, month opening is at the top, some do not move. medusa have a free swimming life, mouth is open downward

coenosteum

coenosteum is the stony skeletal material secreted by the coenosarc, the layer of living material lying between the corallites (the stony cups in which the polyps sit).

explain how gas exchange and waste removal occurs in cnidarians

diffusion

order actiniaria (sea anemones)

ea anemones are a group of water-dwelling, predatory animals of the order Actiniaria. They are named for the anemone, a terrestrial flower. Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Hexacorallia.[1] Anthozoa often have large polyps that allow for digestion of larger prey and also lack a medusa stage.[2] As cnidarians, sea anemones are related to corals, jellyfish, tube-dwelling anemones, and Hydra.

velarium

feature of cubozoa that allows for active swimming and hunting with tentacles up to 15' long

identify the anatomy of cnidarians

gelatinous mesoglea between the ectoderm and the endoderm. gastrovascular cavity is below the pharynx.

identify examples for each class of cnidarians

hydrozoa includes the hydra, obelia, physalia, gonionemus, man of war scyphozoa includes the moon jelly, sea nettle, and lion's mane jellyfish cubozoa includes chironex and irukandji anthozoa includes sea anemones and corals

basal plate

in anatomy of the sea anemone, the surface opposite to the mouth, and generally serves to attach the anemone to the substrate upon which it lives.[1] It is composed of a thin tissue plate and is used by the animal to adhere to and move across the surface.

mesoglea

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

identify general characteristics of cnidarians

includes hydrozoans, jellyfish, and sea anemones, and corals. mostly marine. radial symmetry. diploblastic. gelatinous mesoglea between the ectoderm and the endoderm

endoderm

innermost germ layer; develops into the linings of the digestive tract and much of the respiratory system

nerve net

loosely organized network of nerve cells that together allow cnidarians to detect stimuli

describe how cnidarians move and when in the lifecycle they move

medusa move via epitheliomuscular cells which contract and push against the water. water currents and wind effect movement. polyps move by somersaulting from base to tentacles or like an inchworm

describe the structure of a cnidocyst and explain how a cnidocyst works

nematocysts are produced by cnidocytes. roles in feeding, defense, and attachment. fire when cnidocil is triggered. many contain a toxin that paralyze the prey and destroys its cell membranes.

describe the nervous system of cnidarians

nerve cells are located below the epidermis near the mesoglea and they interconnect to form a nerve net. this sends nerve impulses throughout the body. senory structures are distributed throughout the body and include mechanoreceptors and chemoreceptors

ectoderm

outermost germ layer; produces sense organs, nerves, and outer layer of skin

describe the different methods used by cnidarians to reproduce

sexual reproduction is in most dioecious (each one is of one sex). sperm and sometimes eggs are released into the gastrovascular cavity, then into the water. embryo develops into a planula (ciliated, free swimming larvae). planula attaches to substrate and forms a polyp. asexual reproduction is when polyps form more polyps and medusa in some species by budding.

statocyst

small, fluid-filled chamber that tells an arthropod if it is right side up or upside down (analagous to our inner ear)

cnidocyst

specialized cell in cnidarians that functions in defense and capturing prey

identify and compare the characteristics of the four classes of cnidarians

the class hydrozoa are marine and freshwater, polyp, both types of reproduction the class scyphozoa are all marine, medusa, both types of reproduction the cubozoa are all marine, medusa, have both types of reproduction the class anthozoa are all marine, colonial or solitary polyps, both type of reproduction

planula

the free-swimming, ciliated larva of a cnidarian

explain how cnidarians feed

most feed on small crustaceans and small fish. prey is engulfed or captured and paralyzed by nematocyts and dragged into the mouth area

basal disc

organism's base, secretes a sticky substance that allows it to attach itself to surfaces

strobilation

"form of asexual reproduction consisting of the spontaneous transverse segmentation of the body

budding

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

calcium carbonate

CaCO3

nematocyst

Stinging structure within each cnidocyte of a cnidarian that is used to poison or kill prey.

ocelli

simple eyes

identify and compare the characteristics of the three orders of anthozoans and identify examples of organisms from each class

the order actiniana are polyp and live in tropical cold waters venus fly trap anemone the order scleractinia are polyp and live in warm tropical water coral reefs the order alcyonacea are polyp and live in water with intense light

explain why cnidarians are more advanced than poriferans

they have true tissues and a nervous system

explain how a hydrostatic skeleton works to support a cnidarian

water in the gastrovascular cavity supports the body.

scyphistoma

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