Vertebrates - Vertebrates / Mynxi

Question 1

what are the derived characteristics of the vertebrae clade?

Answer 1

-chordates, but have now evolved with vertebrae
-2+ sets of hox genes
-have a skull and a vertebrae that encloses a spinal cord
-has cephalization: concentration of sensory organs at “head” region
-has a closed circulatory system

Question 2

what are the characteristics of the mynxi class?

Answer 2

-jawless hagfish, marine vertebrates
-has a head with a skull, eyes, brain, etc
-lacks “true bones” - only basic vertebrae

Question 3

what are the characteristics of the petromyzontida class? what is an animal found in this class?

Answer 3

-includes lampreys
-jawless vertebrates
-have segments of cartilage surrounding the notochord and partially over the dorsal nerve cord
-found in marine and freshwater habitats