1. Vertebrates

2. Characteristics Dorsal hollow nerve cord Notochord
Pharyangeal gill slits (pouches)
Post anal tail

3. Characteristics to Consider
Poikilothermic vs. Endothermic Types of Reproduction Vertebrae structure Body Covering Economic Importance

5. Classes
Hagfish (teeth of karatin, unpaired fins, cartiledge skull, no vertebrae, scavengers, produce liters of slime)
Chondrichtheyes (sharks, skates, rays)
Lampreys
Ray-finned
Lobe-finned
Amphibians
Reptiles
Birds
Mammals

6. Chondrichthyes
Cartiledge skeleton, some calcified in scales and teeth.
If stops swimming will sink (stores lots of oil in liver). Some rest on seafloor and must pump water across the gills
Good vision but no color
Nostrils for smelling
Electric field sensation in skin of head
Whole body senses “sound”
Internal fertilization, eggs hatch inside of some sharks

7. Lobe-finned
Rod shaped bones with thick muscles around pectoral and pelvic fins
Rare fish, lungfish

8. Ray finned “Oesteichthyes”
Ray finned: Calcium phosphate bone 5 pairs of gills with operculum Swim bladders to control boyancy Bony scales with mucus secreting glands Lateral line