Transcript Phylum Cnidaria - Conackamack Middle School

Phylum Cnidaria
Pages 307-311
CNIDARIANS“STINGING CELLS”
• SEA JELLIES
• SEA
ANEMONES
• CORALS
• HYDRA
Just the facts…
• CARNIVORES
• STINGING CELLS CALLED
NEMATOCYSTS
• HOLLOW CENTRAL
CAVITY
Body Characteristics
• Body Symmetry: Radial
• Cell Organization: Cells form into musclelike tissues, no organs or organ systems
• Reproduction: Sexual and Asexual
• Body Development: Zygote to Larva to
Polyp to Adult
Cnidarian Anatomy
POLYP
• SHAPED LIKE A VASE
• MOUTH OPENING AT
TOP(ONE OPENING)
• MOST DO NOT
MOVE AROUND
(sessile)
HYDRA
Cnidarian Anatomy
MEDUSA
• BOWL-SHAPED
• FREE SWIMMING
• MOUTHS OPEN
DOWNWARD
SEA JELLY
HOW CNIDARIANS FEED
The Lion's Mane
Jelly is a venomous
SEA JELLY which can sting
people
with its long tentacles
• CAPTURES PREY
USING STINGING
CELLS CALLED
NEMATOCYSTS
• TENTACLES PULL
FOOD INTO ITS
MOUTH.
• FOOD IS
DIGESTED IN ITS
CENTRAL CAVITY
AND EXPELLED
THROUGH ITS
MOUTH
CNIDARIAN
REPRODUCTION
SEXUAL
ASEXUAL
• SOME CARRY BOTH
SPERM AND EGG.
• SOME ARE EITHER
MALE OR FEMALE
• BUDDING
• SPLITS INTO TWO
Throughout its life, the Sea Jelly is found in both
a polyp and a medusa form.
Sea Jellies
• Sea jellies are invading!
CORAL
• A coral colony
consists of
hundreds or
thousands of tiny
polyps. Each polyp
is an individual
animal (basically a
small anemone) but
they live together
as a group.
Coral Reefs
• Reefs are made
when coral
attaches itself to
the ocean floor.
• When it dies its
hard skeleton is
left behind.
• The skeletons
build up and form
large masses.
Australia's Great Barrier Reef
SEA ANEMONE
• These flower-like
animals resemble
plants, but they
have a mouth
at the center of
their tentacles,
and a primitive
digestive system
The Tealia anemone.
Hydra
Hydra reproduce by budding
• 3-8mm in length
• Live in fresh water
• Live in both body
structures
throughout their life
– Polyp
– Medusa
• Mouth surrounded by
tentacles
• If disturbed, a
barbed thread and
poison is ejected
from the nematocyst