Keragaman Bulu Babi (Echinoidea) di Perairan Pantai Pulau ...
General Characteristics Spiny skinned Lack segmentation...
Transcript of General Characteristics Spiny skinned Lack segmentation...
General Characteristics Spiny skinned
Lack segmentation
Radial symmetry
Water vascular system
• All marine
• Test made of calcium plates with
protruding spines
• Bilateral, free-swimming larva to sessile
adult
• Adults have pentaradial
(5 part) symmetry
• Separate sexes
Capable of extensive regeneration
• Ventral surface called the oral surface &
where mouth is located
• Dorsal surface known as aboral surface
& where anus is located
• Have a nervous system, but no head or
brain in adults
• No circulatory, respiratory, or excretory
systems
• Have a network of water-filled canals
called the water vascular system to
help move & feed
• Tube feet on the underside of arms
help in moving & feeding
• One-way digestive system consists
of mouth with oral spines, gut, &
anus
Class Asteroidea – sea stars
C. Ophiuroidea – brittle stars
C. Echinoidea – sea urchins/sand dollar
C. Crinoidea – sea lily/feather star
C. Holothuroidea – sea cucumber
Echinoderm Classification
C. Asteroidea – starfish or sea stars
• Usually along shorelines
• Come in a variety of colors
• Prey on bivalve mollusks such as
clams & oysters
• Have 5 arms that can be regenerated
• Arms project from the central disk
•Have pedicellariae or tiny, forcep-like
structures surrounding their spines to help
clean the body surface
• Reproduce sexually & asexually
• Have external fertilization
• Females produce up to 200,000,000
eggs per season
Examples:
Atlantic Sea star: east coast
Bat Star : west coast
Sun Star: 15 to 20 arms, Pacific coast
Crown of Thorns: up to 80 cm, 4-5cm
spines, Great Barrier Reef
Class Crinoidea - sea lilies &
feather stars
FEATHER STAR
SEA LILY
• Have a long stalk with branching arms
that attach them to rocks & the
ocean bottom
• Can detach & move around
• May have 5 to 200 arms with sticky
tube feet to help capture food (filter
feeders) & take in oxygen
• Common in areas with strong currents
& usually nocturnal feeders
Class Ophiuroidea – brittle stars
• Largest class of echinoderms
• Live on the ocean bottom beneath
stones, in crevices, or in holes
• Have long, narrow arms
• Arms readily break off & regenerate
• Move faster than starfish
• Feed by raking in food with arms or
trapping it with its tube feet
Class Echinoidea – sea urchins &
sand dollars
• Internal organs enclosed by
endoskeleton or test made of fused
skeletal plates
• Body shaped like a sphere (sea urchin)
or a flattened disk (sand dollar)
• Lack arms
• Bodies covered with movable spines
• Have a jaw-like, crushing structure
called Aristotle's lantern to grind food
Sea Urchins:
* Spherical shape
* Live on ocean bottom
* Scrape algae to feed
* Long, barbed spines make venom
for protection
Sand Dollars:
* Flattened body
* Live in sand along coastlines
* Shallow burrowers
* Have short spines
Class Holothuroideasea cucumbers
• Lack arms
• Shaped like a pickle or cucumber
• Live on ocean bottoms (hide) in caves
during the day
• Have a soft body with a tough, leathery
outer skin
• Five rows of tube feet run lengthwise
on the aboral surface of the body
• Have a fringe of tentacles (modified
tube feet) surrounding the mouth to
sweep in food &
•water
• Tentacles have sticky
ends to collect
plankton
•Show bilateral symmetry
•Can eject parts of their internal organs
(evisceration) to scare predators;
regenerate these structures in days
The Giant California Sea Cucumber (up to 40cm)