PHYLUM CNIDARIA Flashcards
Takes its name from cells called cnidoctes,
which contain stinging organelles
CNIDARIA
(formed only by cnidarians)
nematocysts
they are widespread in marine habitats and few in
freshwater
CNIDARIA
they are mostly sessile/slow swimming/slow moving
CNIDARIA
Found mostly in shallow marine habitat
(warm temperatures and tropical regions)
CNIDARIA
where are Cnidariansmostly found?
shallow marine, warm temp and tropical regions
cnidarians takes its name from cells called
cnidocytes
Bodies have distinct tissues but no
organs
are nearly all marine
Cnidarians
are diploblastic
Cnidarians
how many germ layers do cnidarians have
2 germ layers
what are the two germ layers of cnidaria
Ectoderm (epidermis) and endoderm (gastrodermis)
Ectoderm
(epidermis)
endoderm
(gastrodermis)
gelatinous material between the two germ layers
(mesoglea)
body plan of cnidaria
Radial Symmetry
what end do cnidaria have
oral and aboral
Contains oral and aboral end but no
definite end
Two basic types of individuals of cnidaria:
polyps and medusae
Body with two layers:
epidermis and gastrodermis with mesoglea
with single opening that
serves as both mouth and anus;
Gastrovascular cavity:
what cavity do cnidaria have
Gastrovascular cavity
extensible
tentacles usually encircling the mouth or oral
region
Gastrovascular cavity
Gastrovascular cavity: with single opening that
serves as both
mouth and anus
extensible
tentacles usually encircling the — or ————
mouth or oral region
4 class under phylum cnidaria
class Hydrozoa
class Anthozoa
class Cubozoa
class Scyphozoa
(most variable class)
CLASS HYDROZOA
(“true jellyfish”)
CLASS SCHYPHOZOA
(cube jellyfishes)
CLASS CUBOZOA
(corals and sea anemones)
CLASS ANTHOZOA
has 200 species – all marine
Class Scyphozoa
has 4 orders
Class Scyphozoa
example is Sea wasps
Class Cubozoa
has One order and 2 families
Class Cubozoa
has 7 orders
Class Hydrozoa
has over 2,700 species
Class Hydrozoa
this class is All marine
Class Anthozoa
About 2/3 of all described cnidarians are contained in this class
Class Anthozoa
has 15 orders
Class Anthozoa
3 order under class Hydrozoa
Order Hydroida
Order Siphonophora
Order Hydrocorallina
2 subclasses under Class Anthozoa
Subclass Hexacorallia
Subclass Octocorallia
According to pre-molecular phylogenies, the ———– and —— were grouped either separately or together to form the RADIATA
Cnidaria and Ctenophora
- According to pre-molecular phylogenies, the Cnidaria and Ctenophora were grouped either separately or together to form the RADIATA,whereas all of the ‘higher’ animals were grouped within the
Bilateria
it was theorized that ——– were considered to be basal to the Anthozoa,Cubozoa and Scyphozoa
Hydrozoa
it waa theorized that Within the phylum Cnidaria, the Hydrozoa were considered to
be basal to the
Anthozoa,Cubozoa and Scyphozoa
the bi-radial or bilateral symmetry of anthozoans could be interpreted as having independently evolved within the
Cnidaria
