Phylum Cnidaria upto class

1. TOPIC : CLASSIFICATION OF PHYLUM
CNIDARIA UPTO CLASS

2. CLASSIFICATION OF PHYLUM CNIDARIA
Class Hydrozoa
• Fresh water as well as marine.
• polyyp and medusa often show polymorphism and
metagenesis.
• Mesogloea is acellular.
• Gastrovascular cavity is undivided.Gonads are
ectodermal and shed.

3. • Gametetesgametes directly surrounding water into the surrounding water.
• Cnidoblast is present only in epidermis.
• Examples, Hydra (fresh water polyp), Physalia (Portuguese man of war;
neurotoxic, gas gland .

4. FIGURE OF HYDRA AND PHYSALIA

5. CLASSIFICATION OF PHYLUM CNIDARIA UPTO
CLASS
• It include over 9,000 species
• These are mostly marine.
• Important in coral reef.
• These also called“the stingers” because their tentacles
• are present near the mouth bearing stinging cells called
Cnidoblast or cnidocytes composed of nematocysts.

6. CHARACTERISTICS OF PHYLUM CNIDARIA
• Radial or Biradial symmetry
• Tissue level organization and Diploblastic.
• Mesoglia is present.
• Gastrovascular cavity.
• Nervous system in the form of nerve net.
• Cnidocytes for defense , feeding and attachment.
• Oral and Aboral end.

7. • Respond to stimuli from all directions
• Examfishples: Hydra , Obelia, jell fish etc
•

8. • Class Scyphozoa:
• Extensively marin
• Medusa form is most common.
• Mesoglia is thick, gelatinous and contain cells.
• Gastrovacular cavity is undivided.
• Gonades are endodermal and shed the gametes into digestive track when
escape through mouth.

9. • Cnidoblast is present in epidermis and
gastroderm.
• Example:AureIia( jelly fish,moon
fish),larva
• : Ephyra etc.
• fig :
Aurelia

10. • (3) Anthozoa (Actinozoa)
• Exclusively Marine.
• Only polyp form
• .Mesogloea contains cells and fibers.
• Gastrovascular cavity has compartments, i.e., mesenteries.
• Gonads are endodermal and shed gamete into digestive tract escape via mouth.
•
•

11. • .Cnidoblast is present in epidermis and gastrodermis.
• This class has two types of animals: Anemones (Skeleton absent) Adamisa (Sea
anemone) and Corals (CaCO3 skeleton) – Pennautula (Sea pen), Gorgonia (Sea
fan).Gastrodermal in origin; medusa cuboidal in arine, Chirones, Fleckeri,
charybdea.
• fig: Sea Anemone

12. • 4) Class Cubozoa (ku”bo-zo’ah)
• Medusa prominent in the life history, polyp small: gametes gastrodermal in origin,
medusa cuboidal in shape with tentacles that hang from each corner of the bell:
marine, Chirones, Fleckeri, charybdea.
• fig:charybdea