Vertebrates Flashcards
1
Q
Amphibians
A
3 clades:
- Salamanders
- Frogs
- Caecilians
2
Q
Salamanders
A
- Amphibians without tails
- Some aquatic, some terrestrial
3
Q
Caecilians
A
- Legless, nearly blind, resemble earthworms
- Absence of legs is a derived trait evolved from vertebrates with legs
4
Q
Cuticular respiration
A
Gas exchange through the skin
5
Q
Amniotes
A
- Tetrapods that have a terrestrially adapted egg
- Reptiles, birds, mammals
- Amniotic egg was key adaption to life on land
- Relatively impermeable skin
6
Q
Reptiles
A
- Scales create waterproof barrier
- Most lay shelled eggs on land
- Ectothermic (absorb external heat)
7
Q
Birds
A
- Archosaurs
- Almost all anatomy has undergone modification in their adaption to flight
- Lack of urinary bladder
- No teeth
8
Q
Mammals
A
- Amniotes that have hair and produce milk
- Endothermic
- Large brain
- Did not undergo adaptive radiation until after the Cretaceous
9
Q
Characteristics of Chordates
A
(Bilaterian animals, all vertebrate)
- Notochord
- Dorsal, hollow nerve cord
- Pharyngeal slits
- Post-anal tail
10
Q
Notochord
A
Rod between digestive tube and nerve chord
-Provides skeletal support
11
Q
Pharyngeal Slits/Clefts
A
Filter-feeds
Gas exchange
Develop into parts of ear, head and neck in tetrapods
12
Q
Post-anal Tail
A
- Greatly reduced during embryonic development
- Provides propelling force in aquatic species
13
Q
Hox-Genes
A
Control organismal development
-Critical for proper development
