CHARACTERISTICS
• Inter-cell connections
• Carpet-like basement membranes
• Muscles
• Nerve net
• Statocyst
• Hydrostatic skeleton
ANATOMY
• Tentacle
• Nematocyst
• Mouth
• Gastrovascular cavity
• Bud
• Ocelli
DIGESTION
Eating-
Digestive waste-
• Predation
• Enzymes reduce prey to slurry
• absorb dissolved chemicals
• Gastroderm cells absorb nutrients
• filter food particles from water • Indigestible remains of prey go out
mouth
• Two-way digestion
RESPIRATION
•
no respiratory organs
•
Gas exchange over body surface
•
Some pump water in and out of digestive cavity without opening mouth
INTERNAL TRANSPORT
•
Do not have a organized internal transport
•
Large gastrovascular cavity carries partially digested food through body
•
Do not have any blood
•
Gellationous material throughout their body
•
The gellationous material is a storage unit for oxygen
EXCRETION
•
Prey is broken down into slurry by enzymes
•
Absorbs the nutrients
•
After absorbed cells digest nutrients that takes a few days
•
Releases the Indigestible remains out of the mouth
•
Water currents remove cells’ internal processes (ammonia)
RESPONSE
•
•
Nerve net
Special cells cause contractions of muscle-like tissue
• Movement of tentacles during prey capture
•
Sensor organs
•
No brain
•
No eyes
MOVEMENT
•
Only move when they are at the jelly fish stage.
•
Hydrostatic Skeleton
•
Some use jets to propel them
•
Some are sessile
•
Some sea anemones can slowly creep over rocks
REPRODUCTION
•
Sexually
•
Mass spawnings can make the water cloudy from so much gametes
•
Water temperature lighting conditions trigger the spawning
•
Asexually
•
Polyps bud and occasionally split down the middle or above base
•
Medusa split down the middle
•
Larva stage, Polyp stage, Polyp strobilates, and Medusa stage
1-3 larva searches for site
4-8 Polyp grows
9-11 Polyp strobilates
12-14 Medusa grows
EXAMPLES
•
Sea Anemone
•
Jellyfish
•
Corals
•
Sea Pens
•
Box Jellies
FACTS (AKA FUN FACTS)
•
The word Cnidaria comes from the Greek word “cnidos” that means stinging nettle
•
Clownfish and Sea anemones have a symbiotic relationship
•
Urinating on a jellyfish sting could make it worse or make it better
•
Most corals do sting
•
130 different species have been recorded in Sydney Harbor
•
Nematocysts fire tiny harpoon-like spears loaded with venom into prey.
•
The firing of nematocysts is the fastest reaction in the animal kingdom.
LITERATURE CITED
•
http://en.wikipedia.org/wiki/Cnidaria#Feeding_and_excretion
•
http://cnidarianh.blogspot.com/2007/02/feeding-respiration-excretion.html
•
http://cnidarianh.blogspot.com/2007/03/movement.html
•
https://www.boundless.com/biology/textbooks/boundless-biology-textbook/themusculoskeletal-system-38/types-of-skeletal-systems-215/hydrostatic-skeletonexoskeleton-and-endoskeleton-812-12051/
•
http://cnidarianh.blogspot.com/2007/02/internal-transport.html
•
http://phylum-cnidaria.wikispaces.com/FUN+FACTS
•
http://w3.shorecrest.org/~Lisa_Peck/MarineBio/syllabus/ch7invertebrates/Inver
twp/invert_wp_05/cnidaria/miles1/Cool.htm