Chordates Flashcards
What is a stomochord?
Foregut pouch in Hemichordates, doesn’t provide structure.
Why are hemichordates no longer considered Chordates?
Have no notochord (stomochord instead)
Which chordate phyla has an endostyle?
Urochordates (Tunicates)
A ____ secretes mucous sheets used to trap food particles within the cilia lined pharynx.
Endostyle
Tunicates are different to Porifera because….
tunicate larvae possess all 4 chordate characteristics.
Adult ___ retain a notochord
Cephalochordates (Lancelets)
How do Cephalochordates feed?
Filter feeding
Which subphlya uses a oral hood covered in buccal cirri to filter feed?
Cephalochordates (lancelets)
What are myomeres?
visible muscle blocks in Cephalochordates
How are urochordates different to cephalochordates?
Muscles attachment to the endoskeleton is an important characteristic of all chordates. T/F?
True?
Which two subphyla are acraniates?
Urochordate (tunicates) and Cephalochordates (Lancelets)
The gill slits in Lancelets (cephalochordates) function for?
Filter feeding
Adult Urochordates retain which chordate features?
Gill slits
Myxini are classified as vertebrates because of the presence of?
A cranium
Hyperoartia have a ______ while Myxini do not.
cartilaginous skeleton
The only vertebrate class to have no endoskeleton are the ____
hagfish (myxini)
What is Paedomorphosis?
Free swimming larvae with all 4 chordate features
What does homologous mean?
Similar structures in different taxa derived from a common ancestor
Ascidian larvae belong to which subphyla?
The ____ is the core of the endoskeleton
vertebral column
The ___ provides support for, and protects the dorsal hollow nerve cord and is used as a site for muscle attachment
vertebral column
“<b>What are the 4 features that unite chordates?</b>”
<div> <div> In last week’s practical you learned the features that unite the chordates as a group:<br></br><ol> </ol><ul> <li> <div>Notochord </div> </li> <li> <div>Hollow dorsal nerve cord </div> </li> <li> <div>Pharyngeal slits (and bars) </div> </li> <li> <div>Post anal tail</div> </li> </ul> </div> </div>
Ascidian larvae belong to which subphyla?
Subphylum Urochordates (tunincates)