Bio 123: PP14 Material Flashcards
(32 cards)
What falls under Deuterostomia?
Echinodermata
Chordata
What are the major characteristics of Enchinoderms?
-They are deuterostomes
-They have a water vascular system that they rely on for locomotion, food/waste transportations, and respiration
-Live in marine habitats
-Have evolutionary reversals
-They are triploblastic
-They have an endoskeleton that contains millions of calcium carbonate components called ossicles
-They have a complete digestive system
-They can regenerate tissues
-Asexual reproduction by fragmentation
-Have blood vascular system what is reduced and have body fluid circulation by cillia
What are the evolutionary reversals of echinodermata?
-They have radial symmetry
-Have radian nerves (do not have a CNS)
-They have little to no cephalization
-They do not have excretory organs
What are Ossicles?
They are spines/spicules (similar to sponges) that is used for protection
What are the classes of Enchinodermata?
-Asteroidea (Sea Stars)
-Crinoidea (Sea lillies, feather stars)
-Ophiuroidea (Brittle Stars, basket stars)
-Echinoidea (sea urchins, sand dollars)
-Holothuroidea (Sea cucumbers)
Brittle stars
Typically have no symmetry
Radial Animals
Cannot follow dorsal, ventral, posterior, and anterior classification
What body classification do radial animals use?
Aboral surface and the Oral Surface
What is the madreporite
It serves as the entrance to the water vascular system of the organisms
What are the general body parts on the aboral surface of a asteroidea?
-Central disk
-Madreporite
-Anus
-Arm
What are the general body parts on the oral surface of an asteroidea?
-arms
-mouth
-spines
-tube feet
-Ambulacral grooves
-Sensory tentacles
Ambulacral grooves
Give each arm their hardened structure
Spines
Are used for protection
Sensory tentacles
@ the end of each arm and are used for tactile touch as they move around in their environment
Tube Feet
Allows asteroidea to move
Explain the water vascular system of an Asteroidea
-Water enters through the madreporite
-It then moves into the ring canal
-Once in the ring canal it moves into the different radial canals that each arm has
-From the radial canal it goes into the tube feet
-Water can also exit through the madreporite
What are some additional characteristics that sea stars have?
They have sensory tentacles, radial nerves, and the ability of regeneration
Why do sea stars undergo autotomy?
To protect against viruses, to escape predators, and for reproduction.
What is included in the Crinoidea Class?
The sea lillies and feather stars
What are characteristics of crinoidea?
-Have no symmetry
-Includes about 625 extant species
-Have a mobile larval stage
-Relatively sessile
-Live in deep water
-Metamorphic stages go from its sessile stage to its motile form.
What is included in the class Ophiuroidea?
-The brittle stars and the basket stars
What are the characteristics of Ophiuroidea?
-Not very mobile
-motion is limited
-Includes 2000 extant species
-Live in benthic marine habitats
-Have long slender arms
-Have tube feet without suckers
-Madreporite is on the oral surface
Define Benthic
Anything occurring or associated with the bottom of a body of water
What is the major difference between Brittle stars and sea stars?
Brittle stars have their madreporite located on the oral side of their body and sea stars have the madreporite located on the aboral side.
