1. Introduction to Fish

2. What makes a fish a fish?

3. Jaws/ Mouths Terminal: Opens at midline
Superior: Opens towards top of midline
Inferior: opens downwards from midline

4. Scales Cycloid: Fish with smooth fins Ctenoid: Fish with bristled fins
Ganoid: Primitive fish (gar or sturgeon)
Placoid: Skin teeth or dermal denticles (sharks and triggerfish)

5. Gills Respiration (Oxygen & carbon dioxide exchange).
Underneath gill openings, slits or operculum

6. Fins Dorsal (2): Stabilization Pectoral (2): Steering & stopping
Pelvic (2): Stabilization
Caudal (1): Propulsion & steering
Anal (1): Stabilization

7. Swim Bladder Buoyancy control
Some benthic (bottom) fish do not have a swim bladder
Sharks use their oily liver

8. Lateral Line Sensory for touch
Fluid filled bulbs that sense water around the fish

9. There are 3 classes of fish

10. Agnatha Fish without jaws No scales 7-14 gill openings Very primitive
Hagfish or Slime Eel: marine fish, scavengers
Lamprey: Parasitic freshwater fish.

11. Chondrichthyes Cartilage fish Well-developed jaws 5-7 gill slits
Paired fins
Placoid scales
Sharks, skates, rays and Chimaeras

12. Osteichthyes Bony Fish Paired fins Gill cover (Operculum)
Most have scales
Tuna, damsels, triggerfish, etc.