### animal:

Echinoderm
* All echinoderms are able to regenerate arms, visceral and gonadal tissue
  - deuterostomes
* All echinoderms are marine and benthic
  - organisms
* All echinoderms are marine, living in the ocean
  - many live in tide pools
  - display penatamerous radial symmetry
  - have an internal bony skeleton
* All echinoderms have five-part radial symmetry
  - unique features
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* Illustrates common characteristics of echinoderms such as sea cucumbers and starfish.
* Many echinoderms can also form suckers on the ends of their tube feet
  - regenerate body parts that have been injured or broken off
  - have remarkable powers of regeneration
* Most Echinoderms are either male or female, although some are hermaphrodites.
* Most echinoderms achieve radial symmetry
* Most echinoderms are dioecious
  - mobile unlike many of their pentameral peers
  - of one sex, and reproduce by shedding their gametes directly into the water
  - sessile or sedentary marine forms with radial symmetry as adults
  - develop via bilaterally symmetrical larvae
  - digest food
* Most echinoderms display characteristics
  - similar characteristics
* Most echinoderms have arms
  - arrangements
  - exoskeletons
  - healthy appetite
  - mouths
  - organs
  - sense organs
  - sides
  - skin
  - spiny skin
  - structures
* Most echinoderms live in oceans
  - salt water
  - occupy habitats
  - possess coeloms
  - spawn directly into the sea
  - stay in places
  - survive years
* Some Echinoderms even use other animals as homes such as the skin of other fish
  - echinoderms are carnivorous and scavenge the ocean floor
* Some echinoderms change body shapes
* Some echinoderms exhibit behavior
  - distinct behavior
* Some echinoderms have ability
  - ages
* Some echinoderms have develop coeloms
  - eyespots
  - impact
  - large impact
  - nerve rings
  - old ages
  - ingest food
* Some echinoderms provide care
  - parental care
* Some echinoderms pump sea water
* Some echinoderms retain ancestral conditions
* Some echinoderms undergo complex metamorphosis
  * live in all parts of the ocean, but mostly on the sea floor. They are extremely common near the shore, and on reefs
* also have amazing powers of regeneration.
* are all marine and nearly all are benthic, meaning they live on the sea floor
  - among the most distinctive of all animal phyla
  - amongst the most visually stunning of all fossil finds
  - an ancient phylum with a huge fossil record
  - bottom-dwelling marine invertebrates
  - carnivores
  - characterized by their radial symmetry, water vascular system and internal skeleton
  - dioecious with sexual reproduction and external fertilization
  - either filter feeders, substrate eaters or carnivores
* are either male or female and become sexually mature after about two to three years
  - enterocoelous coelomates with a pentaradiate form and no definite head or brain
  - exclusively marine organisms possessing spiny skin
  - fairly advanced invertebrates
  - gonochoristic and fertilization is usually external
* are great animals to use to study development
  - at regenerating body parts
  - known for their pentaradial symmetry
* are marine animals with radial symmetry, spiny endoskeleton, and tube feet
  - spiny skin and five-fold radial symmetry
  - invertebrates that inhabit every conceivable ocean environment
  - more closely related to chordates than any of the other invertebrate phyla
  - often difficult animals to kill and many have well developed powers of regeneration
  - pentaradially symmetrical and have an endoskeleton composed of calcareous ossicles
  - protected through their spiny skins and spines
  - radially symmetrical animals that are only found in the sea
* are radially symmetrical as adults
  - symmetrical, like cnidarians and comb jellies
  - relatives, although distant ones, of the vertebrates
  - scavengers of decaying matter on the sea floor
  - small aquatic animals only found in salt water
  - spiny skinned animals found only in marine environments
  - spiny-skinned animals
  - the only animals that have many tiny tubelike structures called tube feet
* are very different
  - important in both the environment and to people as well
* begin life as bilaterally symmetrical larva.
* can look either like a starfish or a sea urchin.
* contain a complete digestive system, with a mouth and anus.
* exhibit a variety of body plans.
* generally are very casual about re- production
  - occur on the sea floor, usually feeding on other animals or detritus
* have a a poorly developed respiratory system
  - brain, although it is very small
* have a hydraulic system of locomotion called the water vascular system
  - relatively big gut area
  - simple digestive system with a mouth, stomachs, intestineand anus
  - sub-epidermal nerve net running all over their body
  - very long fossil record
  - water vascular system, which system of closed tubes that includes tube feet
  - well-developed gut, while the nervous and circulatory systems are quite simple
  - extensive powers of regeneration of lost or injured parts
  - no brain , although some do have ganglia
  - radial symmetry , many having five or multiples of five arms
* have specialize organs
* includes brains
  - cell membranes
  - cells
  - corpi
  - cytoplasm
  - faces
  - heads
  - nuclei
  - plasma membranes
  - sections
  - skulls
  - vacuoles
* inhabit depths ranging from shallow waters at tide lines to the deep sea.
* is an invertebrate
* lack body segments, and most have radial symmetry as adults
  - respiratory and excretory systems
* live in all parts of the ocean , but mostly on the sea floor
  - either freshwater or ocean water
  - marine habitats
* maintain an important fluid in the body cavity, taking the place of blood.
* make excellent throwing stars
  - up the echinoderm phylum, Echinodermata
* move by odd little hydraulic structures called tube feet.
* possess a complete gut, but no excretory organ
* release eggs and sperm into the water, where fertilization takes place.
* reproduce by laying eggs that develop into larvae and swim freely.
* spawn into the water.
* use the tube feet for moving, feeding, breathing, and sensing
  - water instead of blood to move food around their body, and to breathe
* usually have a skin-covered skeleton of calcareous plates, often bearing spines
  - five appendages, but there are some exceptions
  - live on the sea floors
  - refer to creatures with little bone structure that live under the sea
+ Echinoderm, General account
  * Echinoderms have a hydraulic water vascular system. This network of fluid-filled canals moves and feeds the animal, and allows gas exchange. There is also a complete digestive tube. They have a simple radial nervous system that consists of a modified nerve net. There are nerve rings with radiating nerves around the mouth extending into each arm. The branches of these nerves coordinate the movements of the animal.
  * This network of fluid-filled canals moves and feeds the animal, and allows gas exchange. There is also a complete digestive tube. They have a simple radial nervous system that consists of a modified nerve net. There are nerve rings with radiating nerves around the mouth extending into each arm. The branches of these nerves coordinate the movements of the animal. Echinoderms have no brain, although some do have ganglia. They usually move with their tube feet, but brittle stars use their arms to pull against rocks. Some feather stars and sea cucumbers can swim.
  * Many echinoderms have remarkable powers of regeneration. A starfish arm cut off will regenerate. A section as small as a single arm, with some central disk and neural tissue, can regenerate the whole organism.