Download Phylum Cnidaria

Chapter 24.3
( pgs. 705-715)
Sponges
and
Cnidarians
Phylum Porifera (“pore-bearer”)
Includes all sponges
(8,000 + species)
Basketball sponge
• Simplest animals
• Asymmetrical
• Lack organs
• Lack a nervous system
Knob sponge
Phylum Porifera



Aquatic – mostly marine
Sessile - can’t move from
place to place
Filter feeders
Volcano sponge
Red sponge
Phylum Porifera


Reproduce both
sexually and…
Asexually
* Regeneration –
reattach, replace
lost parts
* Budding - grow
new sponges
Dead man’s finger sponge
Phylum Porifera
Hermaphrodites produce both eggs and sperm
Sponge dumping gametes
Phylum Porifera

Osculum - opening on some
sponges
 Spicules - sharp, hard, needlelike structures - attachment
Phylum Cnidaria
(“nettles” / tentacles)
Includes jellyfishes, corals,
sea anemones & hydras
Brain coral
Green anemone
Jellyfishes
Phylum Cnidaria
Aquatic –
mostly marine
 Radial symmetry

Flower pot coral
Purple anemone
Phylum Cnidaria
Nerve net –
a simple nervous system
Torch coral
Sun coral
Nematocysts
- tubes in
tentacles - contains poison
Gastrovascular
cavity primitive stomach
Monterey, CA
Phylum Cnidaria

Two basic body forms


Polyp - tube shaped body
Medusa - body shaped
like an umbrella
Red cauliflower coral
Medusa
Moon
jelly
Sea anemone
Club tipped anemone
Pineapple coral
Staghorn coral
Corals
Reproduce:
Sexually
- hermaphrodites
Asexually - budding
Budding hydra
Hydra releasing an egg
Hydra releasing sperm