Vertebrate Chordates

Question 1

Describe the necessary modifications in an invertebrate to become a vertebrate

Answer 1

Muscularisation of the pharynx
(Increased water flow through body)

Cephalisation
(concentration of sense organs at front or organism= Brain)

Evolution of Vertebrate
(backbone becomes axis of body)

Question 2

What happens to the phalangeal slits in vertebrates ?

Answer 2

They become inner ear bones, improving auditory system.

Question 3

What is the neural arch ?

Answer 3

A dorsal hollow for the nerve chord, providing protection.`

Question 4

What is found in the hemal arch ?

Answer 4

A blood vessel

Question 5

The centrum is found between the hemal and neural arches.

What is it a remenant of ?

Answer 5

The notochord,

No longer a flexible chord. We now have repeating units (vertebrae)

Question 6

What is the most abundant vertebrate ?

Answer 6

Bristle mouth fish, in the genus cyclothone.

Question 7

Photophores enable communication between bristle mouth fish in a shoal.
Give the species responsible for this.

Answer 7

Bacteria, have a symbiotic relationship.

Question 8

Give the derived characteristics of vertebrates.

Answer 8

Vertebrate enclosing spinal chord

Elaborate skull

Fin rays, in aquatic forms