The retention by adults of traits previously seen only in the young is important in
developmental biology, and consequently in evolution. It occurs in two ways. In
Chapter 29: Echinoderms and Invertebrate Chordates. Echinoderms ... 3. An
animal that retains its chordate features throughout life is the _____. Need a Hint
Chordata contains two subphylums of invertebrates: Urochordata (tunicates) and
... Seawater enters the tunicate's body through its incurrent siphon. ... Adult
lancelets retain the four key features of chordates: a notochord, a dorsal hollow
nerve ... of Animal Life, Characteristics of Vertebrates, and Characteristics of
... derived characteristics of chordates distinguish them from their ancestors: ...
need not be retained throughout life for an animal to be considered a chordate.
Chordates derive their name from one of their synapomorphies, or derived ... This
is the notochord , a semi-flexible rod running along the length of the animal. ...
Pharyngeal slits are a third chordate feature; these are openings between the ...
Mar 30, 2012 ... Vertebrates retain traces of a feeding apparatus like that of tunicates and
cephalochordates. ... The chordate life cycle begins with fertilization (the union of
sperm and egg). In its primitive form, fertilization occurs externally, in the water. ....
possess gill slits and other features not found in other animal phyl...
In tunicates, the chordate characteristics can be observed only by examining the
... A related group, the larvaceans (Appendicularians), live throughout the life
cycle ... They stick their heads out of the sand and feed somewhat like a tunicate.
... brief periods of swimming, such as when the animal is dislodged from the sand
Nov 21, 2008 ... The higher chordates were built on the foundation of this model ... defining
characteristics of the phylum Chordata, along with the presence of a hollow ...
Lancelets (suphylum Cephalochordata) retain the notochord throughout their
lives ... the hagfish and lampreys, the notochord remains throughout life and ...
... 36: Chemical Coordination, Chapter 37: Immunity, Chapter 38: Animal
Behavior ... For simplicity, however, this text retains the traditional Linnaean
classification, but ... These characteristics are found in all chordates at some
stage of their life ... In the protochordates and jawless vertebrates, it is persistent
This marine animal looks very fish-like with fins, a tail, muscle blocks called ...
This is the one group that retains the Chordate characteristics throughout its life.