Parazoa And Metazoa Flashcards
Platyhelminthes AKA
Flatworm
Nematoda AKA
Round worms
Cnidarians AKA
Coelenterates
What is the single phylum in Parazoa?
Phylum porifera
Porifera AKA
Sponges
Xtics of porifera?
• sponges
• Most primitive multicellular
• Adults are sessile
• Hermaphrodites
• major body opening is EXHALANT( osculum) ••••
What were porifera named based on
Have incessant pores on body surface called OSTIA.
Ostia is linked to inhalant canals.
What is the major body opening in porifera?
EXHALANT — OSCULUM
Why are Porifera often colored?
Due to interactions with symbiotic algae.
What is the layer lining the internal ceolom of Porifera called ?
Gastral layer / choanoderm
What is the choanoderm composed of in porifera?
Collared flagellated cells called CHOANOCYTES
Reproduction is
Asexual and sexual
Amphiloblastula is
One of the diff. larval forms in porifera
Classes under Phylum porifera
Calcarea ( skeleton consists of calcareous spicules)
Hexactinellida (six-rayed spicules)
Demospongiae (no skeleton, jelly filled choanocytes)
Sclerospongiae (leuconoid marine)
What is leuconoid?
Whitish
Porifera means
Bearing pores
Pore - bearing
What is the single phylum in parazoa?
Porifera
Phylum Porifera is also called
Sponges
Which are the most primitive multicellular animals?
Parazoa
Porifera adults are mainly
Sessile and attached to rock surfaces
What is the primary opening in Parazoans/ Porifera?
EXHALANT
Sexual nature of Porifera?
Hermaphroditism
Four phylum under Porifera
Calcarea- calcareous spicules
Hexactinellida- six rayes silíceous spicules
Demospongiae- no skeleton or if present doesn’t have six rayed spicules
Sclerospongiae- leuconoid
Levels of organization in Metazoa
Diploblastic
Triploblastic
Principal opening in Metazoa
Inhalant
What line the ceolom of Metazoa
Endoderm cells NOT choanocytes
Diploblastic body in Metazoa is attained by
Cnidarians (coelenterates)
Phyla in Metazoa
Cnidaria- coelenterates
Mollusca-
Platyhelminthes- flatworms
Nematoda- round worms
Arthropoda
Echinodermata
Xtics of phylum Cnidaria
- coelenterates
- single ceulom called ENTERON
- mouth surrounded by tentacles
- tissue level of organisation
- radial symmetry
- sedentary or free swimmers
- asexual by budding
Nematocysts in Cnidaria serve for
Defense and capture, found on tentacles.
The single ceolom in Cnidaria is
ENTERON for ingestion and digestion
Polymorphism is exhibited by
Cnidaria
What forms do Cnidaria show in polymorphism?
Hydroid(polyp)
Medusoid
The medusoid in Cnidaria are
Free swimming
The hydroids (polyp) forms in Cnidaria are
Sedentary/ solitary/ colonial
The 3 classes under Cnidaria are
Hydrozoa
Schyphozoa
Anthozoa
Xtics of class hydrozoa
- polyp(hydroid) and medusoid forms present
- hydroid is predominant, Medusa the simplest stage
- reproduction by alternation of asexual and sexual phases
Examples of class hydrozoa.
Hydra, Physalia (Portuguese man of war)
Xtics of class scyphozoa
Nematocysts in the ectoderm
No gullet
Exclusively marine
Hydroid stage often absent or reduced to small larvae, gives rise to Medusa by TRANSVERSE FISSION
Examples of class scyphozoa
Aurelia ( jellyfish)
Pelagia
Xtics of class Anthozoa
Exclusively marine
Largest class in Cnidaria
Only polyps/ hydroids occur
Nematocysts in endoderm
Examples of class Anthozoa
Actinia- sea anemone
Astrangia- coral
