Lecture 27: Chordates Flashcards
1
Q
Phylum Chordata traits?
A
Bilateral symmetry
Deuterostomia
Coelom
Segmented
2
Q
Four synapomorphies?
A
Notochord: For support
Dorsal holllow nerve cord: spinal cord
Pharyngeal slits
Post anal tail
3
Q
Cephalochordata (Lancelets)
A
All marine
Adult has chordate states
Segmented
Suspension feeders
4
Q
Vertebrate brain evolved from?
A
Lancelet’s simple nerve cord
5
Q
Urochordata (Tunicates)
A
All marine
Adults dont look like chordates
Use pharyngeal basket to feed
6
Q
Notochord is?
A
Homologous
7
Q
Pikaia?
A
Early chordate
So…no head?
8
Q
Haikouella?
A
eyes and brain, no skull
9
Q
Myllokunmingia
A
Skull but no vert
10
Q
Subphylum Vertebrata?
A
Vertebral column=backbone
Replaces notochord function
Gene dup.: two or more hox gene clusters
Inverts have 1
11
Q
Class myxini
A
Hagfish
All marine
Cranium made of cartilage
12
Q
Class petromyzontida?
A
Lamprey marine and freshwater eyes with lenses but no jaws Skeleton is cartilage Notochord surrounded by cartilage tube partial vert column
