FISH

Phylum Chordata All chordates have for all or part of their lives: A. A notochord - Flexible rod shaped support B. A hollow dorsal nerve cord - Hollow cord that becomes spinal cord C. Gill Slits - Folds of skin D. Post Anal Tail

Kingdom Phylum – Subphylum Class Order Family Genus Species Animalia Chordata Vertebrata Osteichthyes

Class Osteichthyes Bony Fish Scales smooth and overlapping O: Eye Used for sight Many fish in caves have no eyes Eyes on same side of head means they probably stay on bottom of ocean A: First Dorsal Fin B: Second Dorsal Fin Dorsal fins give stability during swimming. The different sections are referred to as rays. # of rays is used in classification D: Caudal Fin Main function is to propel fish forward. E: Caudal Peduncle Contains muscles that help fish use its caudal fin for movement forward. F: Anal Fin Stability in swimming. H/G Anus and Urogenital Pore Exit for wastes Opening for genitals J: Pelvic Fin Stability in swimming I: Pectoral Fin Side to side movement K: Gill Opening L: Operculum (Gill Covering) Gills are used for the exchange of gases from the water to the fish’s blood. Class Osteichthyes only has one gill slit. M: Mouth Used to ingest food N: Nostril Used for smelling food. Probably hunt more with nose than eyes. C: Lateral Line Special line of cells connected to many sensory organs. Helps fish detect small differences in water around them. This is what allows fish to make movements all together as one school.

4 types of scales Ganoid CycloidCtenoid Placoid

Class Chondrichthyes Cartilaginous Fishes – Sharks, Skates, Rays – Main EXTERNAL differences from bony fish: – No Operculum – Only swim forward – Rough Scales

1 st Dorsal Fin 2 nd Dorsal Fin Spike (for defense) snout Gill slits