Vertebrates

Question 1

when did vertebrates originate?

Answer 1

cambrian

Question 2

characteristics of chordates?

Answer 2

notochord - provides skeletal support- becomes skeleton
dorsal nerve cord - becomes the CNS
pharyngeal slits - grooves on outside, for suspension feeding, gas exchange and develop into head in tetrapods
post-anal tail - propelling force

Question 3

what are lancelets and tunicates?

Answer 3

non-vertebrate chordates
lancelets - marine suspension feeders
tunicates - feed via siphons, reabsorb tail, resemble chordates in larval stages

Question 4

what are the aganthans?

Answer 4

jawless vertebrates - hagfish and lampreys

Question 5

what are conodonts?

Answer 5

jawed, soft bodied vertebrate with hooks for catching prey

Question 6

key feature of early jawless vertebrates?

Answer 6

heavily armoured plates

Question 7

what are gnathostomes?

Answer 7

jawed vertebrates with teeth for gripping/slicing