lec 8 Flashcards
Subphylum and Class Anthozoa num of species
7200 spp
Subclass Octocorallia
howmany tentacles
and other things
skeleton?
subclass of anthozoa
-8 tentacles per polyp
-8 gastrovascular septa
-most have calcareous endoskeleton that forms in mesoglea
Subclass Hexacorallia
howmany tentacles
how many other things
skeleton?
subclass of anthozoa
-includes solitary sea anemones and colonial stony corals
-more than 8 tentacles
-gastrovascular septa
multiples of 6 pairs
-calcareous skeleton secreted by epidermis–> considered exoskeleton
shared symmetry of anthozoa
hexaradial/octaradial symmetry
Class Hydrozoa species num
3500 sp
hydroids can be
thecate or naked
Hydroidswhat form dominates
polyp form dominates, solitary or colonial
Class Hydrozoa
whatsspecial abt these mfs
-hydroids
-division of labor in colonial polyps
fire corals
play an important role in coral
reefs; medusa stage reduced
- part of the hydrocorals
chondrophores
and what do they include
-entirely pelagic
-includes
Velella
siphonophores
swimming or floating
polymorphic colonies
polymorphic
multiple medusoid & polypoid forms in one colony
Class Scyphozoa how many spec
true’ jellyfish; ~200 spp
Class cubazoa spc num
20 spc
Class Cubozoa features
-almost square bell
-have complex eyes that can form images
-most potent stings
class staurozoa num spp
50 spp
class staurozoa features
benthic and non ciliated planula that transform to sessile poly that develops to mostly sessile medusa
shared features of medusozoa
medusae(lost in some hydrozoa)
linear mitochondrial DNA
Class Polypodiozoa
class of endocnidozoa
1 species
freshwater, paracitic inside sturgeon eggs
Polypodium
paracites inside sturgeon eggs, spend years inside unfertilized eggs, then laid into water and burst out of eggs as medusoids
Endocnidozoa: Myxozoa sppc numb
2200 spc
Myxozoa features
specialized structures?
all parasitic in invertebrates
have myxospores–> cnida like structures
what causes whirling disease
Myxobolus
cerebralis
shared features of endocnidozoa
obligatory endoparasitism
Feeding in Cnidaria
except for parasites, all knidarians are predators
partially digested food distributed throughout body via
gastrovascular system
undigested waste expelled how?cnidarians
through the mouth
how do many cnidarians supplement diet?
carbohydrates produced by symbiotic algae
:marine cnidarians host zooxanthellae
defences in cnidarians
nematocysts are used
in defense against predators
medical for cniderians
-nematocysts of many species can damage
human skin
-vinegar can inhibit firing
uses for cnidaria for humans
-jellyfish are
consumed as food
-anemones too
-aquarium trade
-tourism
threats to coral reefs
overharvesting, trawling,
excessive nutrient run-off,
warming waters, loss of
zooxanthellae
Phylum Ctenophora spc
130
all marine
Phylum Ctenophora shit
mostly pelagic
suggest possibility of most basal metazoan
Phylum Ctenophora share features with Cnidaria 4
- type of radial symmetry with a clear oral-aboral axis
- diploblastic organization, w a mostly non-cellular middle layer
- gastrovascular cavity that serves
both for digestion and for distribution of food and oxygen - nerve net rather than a centralized nervous
system
Phylum Ctenophora differnet features with Cnidaria 6
- lack cnidocytes
- asexual reproduction rare
- are never colonial
- vast majority are hermaphroditic
and free-spawn both eggs and sperm somtimes self-fertilize - do not have a planula larva, called cydippid
- possess a mouth and maybe a type
of through-gut with two anal pores
Ctenophora distinctive features 4
- adults exhibit
biradial symmetry - Comb rows made of ctenes, formed from paddle-like
groups of cilia - largest animals able to
swim using cilia–> v big cilia - 2 long tentacles covered w coloblasts
- statocyst at aboral end
coloblasts
unique to ctenophore
very adhesive cells for catching prey
statocyst
-organ of balance and orientation
-evolved independently in many invertebrates
whats in statocyst
calcareous statolith is balanced on four tufts of
cilia that are each connected to two comb rows,
if lith presses against shit it sends nervous signal kinda cool
ctenophores feeding
predators
Mnemiopsis
introduction caused crash of fisheries in black sea cuz it eats fish eggs
beroe got introduced too and fucks the mnemiopsis
ctenophore gut
lacking a ‘true’ through-gut
however anal pores are temporary so technically temporary anus and temporary through gut
