Chordates Flashcards
(6 cards)
Chordates
Bilaterian animals that belong to deuterostomia
Bilaterally symmetrical coelomates with segmated bodes.
Most have a vertebral column
Shared Derived Traits of Chordates
Notochord
Dorsal, hollow nerve cord (formed during embryogenesis)
Pharyngeal slits or clefts for filter-feeding and gas exchange
Muscular, post-anal tail
Notochord
A shared derived trait of chordates
Longitudinal flexible rod located dorsally between the digestive trace and the nerve cord
Formed during embryogenesis from mesoderm
Chordate Segmentation
Segmented body plans with highly specialized and distinct body regions
Evolved independently
Develops from the mesoderm that flank the notochord
Cephalochordata
Chordate group
Lancelets are named for their blade like body shape
Marine sedentary suspension feeders that wiggle backwards in the sand to drawn water into their mouths through pharyngeal slits that then exit through the atriopore
Urochordata
Chordates group of Tunicates
Most closely related to lancelates
Invertebrate, sessile chordates
Larval, tadpole, stage resembles suspension feeding chordates but the adult does not look like a chordate
Characterized by tough polysaccharide “tunic” that draws water in and then filters water out to gain food particles
