animal planet review
protosomes
(snails, leeches, ants) blastopore gives rise to the mouth
deuterostomes
(starfish, stingrays, relicans, monkeys) blastopore gives rise to the anal opening
Class Calcarea
3 small marine sponges w spicules composed of calcium carbonate; spicules vary from monoaxonal (needle-shaped) to triaxonal (3 rays), tetraconal (4 rays) & six-rayed; majority of sponges are vase-shaped and drab in color (altho a few bright exist); consist of asconoid, syconoid & leuconoid; Sychpha (Grantia) is a vase-shaped sponge that can live in colonies, is only 1 to 3 cm long and possesses group of monoaconal spicules at osculum entrance; Leucosolenia is a small, branched asconoid sponge
3 classes of sponge:
Calcarea, Demospongiae, Hexactinellida
cnidarian species we might observe in lab:
Hydra sp., Obelia sp., Physalia sp., Gonionemus sp., Daphnus sp., Artemia sp., Aurelia sp., Carybdea sp., Chironex sp., Metridium sp.
one of the most common hydrozoans
Hydra, a small freshwater species
sponge species we may look in lab:
Leocosolenia sp., Sychpha (Grantia) sp., Spongilla sp., Euplectella sp.
typical member of class Hydrozoa:
Obelia, which can exist in both asexual polyp and sexual medusa forms
ctenophora species we might observe in lab:
Pleurobrachia spp, Mnemiopsis spp.
perisarc
a chitinous sheath that protects the stalk
colloblasts
adhesive cells that ctenophores use to capture food
osculum
allows water to be eliminated from sponge
amoebocyte
archaeocyte; cell that moves about in the mesohyl and absorbs, digests and transports food; involved in formation of spicules & spongin
most species of sponge have one of three types of canal systems, which are:
asconoid, syconoid, leuconoid
life cycle of most hydrozoans consists of an ____ and a ____ stage
asexual polyp; sexual medusa
bilateral symmetry
body can be divided into two mirror images (humans, mice, most animals)
coelom
body cavity; 3 distinct arrangements (acoelomates, pseudocoelomates, eucoelomates)
Class Cubozoa
box jellyfishes; medusoid form is prominent, polyp is inconspicuous; bell is cubical and bent; tentacles suspended from four flat pedalia at umbrella corners; venom of box jellyfish extremely cardiotoxic, neurotoxic & dermanecrotic; ex: Tripedalia cystophora and Carybdea spp.
in cnidarians, asexual reproduction can take place through ___, and in some colonial forms the life cycle includes an ____ part
budding; asexual
spicules
calcareous or siliceous crystalline; makes up the skeletal structure of sponges (along w fibrous collagen)
Hexactinellida
called "glass sponge" bc of 6-rayed siliceous spicules that are fused into intricate glass-like lattice; sponges are primarily deep-water marine forms; bodies of sponge usually cylindrical or funnel-shaped; flagellated chambers can be syconoid or leuconoid; ex: Venus flower basket (Euplectella sp.)
tentacles help to ___
capture food, such as small insect larvae, crustaceans and worms
spongocoel
central cavity in sponge; lined with choanocytes
planula
ciliated; larva that develops from embryo which attached to a substrate and develops into polyp form
spongin
collagenous protein
Phylum Ctenophora
comb jellies; solitary, harmless, marine, jellyfish-like animals sometimes called "sea walnuts" or "sea gooseberries"; exclusively marine; exist as medusa only; have colloblasts to capture food and do not possess nematocysts; tentacles are solid w only epidermis; swim by means of comb plates; monoecious, reproducing only by sexual means; many are bioluminescent; ex: Pleurobrachia spp., Mnemiopsis spp.
basal disk
contains specialized gland cells that allow it to attach to a substrate (perhaps a lily pad). in addition, it allows organism to form a gas bubble for floating
enidarians muscular system is made from ____ and ____ cells
contractile ectodermal and endodermal (epitheliomuscular)
body of Hydra
cylindrical tube with its aboral (away from mouth) end forming a slender stalk ending in a basal disk for attachment
eucoelomates
derived from only mesodermal tissues
in cnidarians, gas exchange occurs through:
diffusion
many cnidarians are ___
dioecious (male & female gametes are produced in separate individuals. gametes combine to form an embryo that develops into a ciliated planula. larva eventually attaches to a substrate and develops in polyp form)
hypostome
encircled by tentacles; mouth opens into a gastrovascular cavity continuous with tentacles; testes or ovaries appear as rounded structured on the body
cnidarian digestion is ____ and they have ___ coelom
extracellular; no
choanocytes
flagellated, collar-shaped cells that line spongocoel
acoelomates
flatworms (tapeworms) do not have a coelom between the digestive system and the outer body wall
Class Anthozoa
flower animals; exist as polyps only; colonial or solitary marine organisms; pharynx leads into a gastrovascular cavity divided by eight or more septa; ex: sea anemones, sea fans, sea pens, sea pansies and corals; occur from the intertidal zone of the ocean to great marine trenches sea anemones occur in warm coastal waters; sessile, attaching by their pedal disk to a suitable substrate; cylindrically shaped w a crown of tentacles surrounding mouth; some have separate sexes, others monoecious; feed primarily on fishes; asexual reproduction can occur as fragments of the pedal disk break off (pedal laceration), transverse fission or budding. some have complex symbiotic relationships with other organisms like algae and fish
comb plates
fused cilia that ctenophores use to swim through
mesohyl
gelatinous matrix where sponge cells and arranged
meoglea
gelatinous nonliving substance that exists between cnidarian's epidermis & gastrodermis/endodermis
Phylum Cnidaria
jellyfish; primarily marine invertebrates; majority are sessile; dimorphic (2 body forms): medusa & polyp; radial symmetry; diplobastic; many are bioluminescent; many are dioecious (male & female gametes produced in separate individuals) comprise 4 classes: Hydrozoa (hydras & hydroids), Sychphozoa (true jellyfish), Cubozoa (box jellyfish), Anthozoa ("flower animals")
Class Demospongiae
largest class of sponges; usually brilliantly colored with monoaconal or tetraconal siliceous spicules sometimes bound by spongin; usually leuconoid canal systems; ex: bath sponge (Spongilla spp.) and barrel sponge (Xestospongia testudinaria)
in life cycle of Aurelia..
male and female medusae produce their respective gametes, which undergo fertilization to form a zygote that may be retained on the oral arms of the medusa and eventually becomes a ciliated planula larva. larva lands on suitable substrate and forms a sycphistoma that grows perhaps asexually, buds and forms an asexual strobila. strobila gives rise to swimming ephyra that eventually develop into a medusa
leuconoid canal system
most common and complex type of sponge; form large masses, each member having own osculum; clusters of flagellated chambers receive water from incurrent canals & discharged water exists via excurrent canals & eventually osculum; one species has been estimated to have several million flagellated chambers
cnidarians' nerve net is composed of:
neurites and sensory organs (ex: photosensitive organs for light detection, statocysts for balance)
do cnidarians have a respiratory system?
no
mouth of hydra is located where?
on the hypostome, an elevated portion of the oral end
polyp
one of cnidarians' two body forms; CORAL; consists of tubular sessile body
medusa
one of cnidarians' two body forms; JELLYFISH; resembles upside-down cup w tentacles
enidoblasts
or endocytes; contain nemotocysts
Class Hydrozoa
polyp form is dominant; most are marine; Hydra spp., Obelia spp., Portuguese man-of-war (Physalia physalis)
zooids
polyps used for feeding called hydranths
ostia
pores in sponge
cnidarians exhibit ____ symmetry and are ____
radial; diploblastic
gonangium
reproductive polyps attached to stalk; dioecious medusae bud from these
cnidarians have ______ leading into their digestive system and ___ surrounding mouth.
single opening; tentacles
asconoid canal system
sponges are generally small & tube-shaped; water enters tiny ostia & makes its way to spongocoel, water is filtered and exits via osculum; asconoid sponges are in class Calcarea
syconoid canal system
sponges resemble large versions of asconoid sponges; sponges have tubular body w single prominent osculum, have more complex canal system than asconoid; choanocytes are found in numerous radial canals that empty into the spongocoel lined w epithelia-like cells in syconoid sponges; water w its nutrients enters sponge through ostia into an incurrent canal, then passes through prosopyles into the radial canals where food is ingested by choanocytes. choanocyte flagella force water through apopyles into the spongocoel. filtered water exits the osculum. class Calcarea and Hexactinellida
Phylum Porifera
sponges, which are multicellular yet phylogenetically distinct from other metazoans bc they do not have tissues or organs; vast majority of sponges are sessile marine organisms; simplest of multicellular animals; may be evolved from choanoflagellates
nematocyst
stinging cells that aid in food gathering and defense
Obelia attaches to the substrate via ____ that gives rise to various ___
stolon (rootlike structure); stalks
radial symmetry
symmetry around a central axis (ex: starfish, corals)
pseudocoelomates
the coelom is derives from both the endoderm and the medoderm (rotifers & roundworms)
amoebocytes within mesoglea aid in __, ___, ___, ___, ___ against bacteria.
transport, storage, repair, defense
Class Sycphozoa
true jellyfishes; consists of solitary organisms in which a polyp stage is reduced or absent, dominant stage is a bell-shaped medusa; edge of bell (umbrella) has 8 notches with sense organs; ex: Aurelia spp., Chysaora spp., Cassiopeia spp.
complete digestive tract
tube-within-a-tube body plan (squids, lions)
incomplete digestive tract
what goes in the mouth goes back out the mouth (jellyfish, worms)
in cnidarians, do individual cells perform excretion?
yes