Chordata

Question 1

4 defining features of Chordata

Answer 1

Notochord- still cartilaginous rod that extends along the body
Dorsal- hollow nerve chord
Pharyngeal slits
Post-anal tail

Question 2

Name the two non-vertebrate chordates

Answer 2

Tunicates - sea squirts, sea tulips

Laneclets - amphioxus

Question 3

Agnatha- what are they

Answer 3

Jawless fish
Elongate, slimy and scaleless fish without jaws or paired fins
Hagfish and Lampreys

Question 4

Chondrichthyes- what are they

Answer 4

Cartilaginous fish with paired fins and claspers in males
Sharks, skates and rays
Chimaeras

Question 5

Osteichthyes- what are they

Answer 5

Bony fish with paired fins and swim bladders for buoyancy
Ray-finned
Lobe-finned

Question 6

Amphibia- what are they

Answer 6

tetrapods with moist scaleless skin where gas exchange occurs, they experience metamorphosis and are carnivores as adults
Frogs & Toads
Salamanders
Caecilians - legless (not snakes because they are scaleless)

Question 7

Reptilia- what are they

Answer 7

Tetrapods with scaley skin, they are the first amniotes (animals with no aquatic stage)
Testudines - shelled
Squamata - scaled skin
Crocodilians - flattened snout

Question 8

When did mammals first appear in mass

Answer 8

Cambrian explosion 540-480 Mya