The Deuterostomia II Flashcards
1
Q
Give the characteristics of the generalised Chordate
A
- pharyngeal slits
- endostyle
- dorsal hollow nerve cord
- postanal tail
- notochord
- lateral muscles
2
Q
Describe pharyngeal slits
A
for feeding and gas exchange
3
Q
Give the 3 Chordate Subphyla
A
- Tunicates (Urochordates)
- Cephalochordates (amphioxus)
- Vertebrates
4
Q
Give the 3 Tunicate Classes
A
- Ascidiacea
- Larvacea
- Thaliacea
5
Q
Describe the Ascidians (=sea squirts)
A
- sessile
- filter-feeding blobs
- thick coat of ‘cellulose’ = tunic
- marine
- common
6
Q
Describe Tunicate cellulose
A
- genes came by HGT
7
Q
Discuss Tunicate morphology
A
- mouth
- pharynx
- anus
- stomach
- endostyle
- brain
- gonads
- atrium
- body wall
8
Q
Describe colonial ascidians
A
- compound
- genetically identical (arise by budding)
- many ‘entrances’, one ‘exit’
- usually share one tunic
- branchial siphon lets water in
- common atrial siphon (cloaca) lets water out
9
Q
Discuss Thaliacea
A
- “salps”
- look like sea squirts but NOT sessile
- swim
10
Q
Discuss Thaliacean morphology
A
- pharynx
- pharyngeal slits
- endostyle
- atrium
- gut
- muscle bands
11
Q
Give a Thaliacea
A
- pyrosoma
- colonial thaliacean
- up to 10-20 m long
12
Q
Discuss Larvacea
A
- look like tadpole larvae
that are sexually mature - live in complex gel
13
Q
Discuss Amphioxus
A
- marine
- flter feeders (eat algae)
- very like generalised chordate
