1. The Bony Fish Class Osteichtyes

2. Characteristics of the bony fish Skeleton of bone “Ray-finned” – Slender bony spines supporting fins – Present in most bony fish “Lobe-finned” – Fleshy fins supported by bones – Only 7 known species (lungfish, coelacanth) Can be fresh water, salt water, or both Most have scales

3. COLORATION Chromatophore – pigment controlling organelle in fish – Gives fish their coloration Mimicry Camouflage Disruptive coloration

4. Coloration Patterns

5. RESPIRATION Exchange gas using gills located on either side of the pharynx Gills – feathery, threadlike structures called filaments. Each filament contains capillaries that proved a large surface area for gas exchange. Oxygen-rich water is moved through the mouth and over the gills Operculum – bony protective plate covering gills

6. CIRCULATION Closed circulatory system Single loop system – heart  gills  body  heart 2-lobed heart – Atrium Receives deoxygenated blood from the body and pumps it to the ventricle – Ventricle Pumps deoxygenated blood to the gills and throughout the body.

7. FISH HEART

8. EXCRETION Waste is emitted in the form of ammonia – Gills – Kidneys Filter waste from the blood Control the amount of water in the fish Freshwater fish have dilute urine Marine fish concentrate urine to reduce water loss (through osmosis)

9. RESPONSE Well developed nervous system – Organized around the brain Cerebrum – voluntary activities Olfactory Lobe – interprets odor Cerebellum – coordinates body movement Medulla Oblongata – controls internal organs Well developed eyes Lateral line – Fluid-filled line on side of body that senses pressure changes in the surroundings

10. MOVEMENT S-shaped movement caused by alternating muscle contractions along the spine Paired fins for movement – Pectoral fins – Pelvic fins – Dorsal fins – Caudal fins

11. FISH FINS

12. REPRODUCTION Eggs may be fertilized externally (oviparous) or internally (ovoviviparous) Oviparous – eggs fertilized externally, developing embryo obtains nutrients from a yolk Ovoviviparous – eggs fertilized internally, developing embryo obtains nutrients from a yolk. Young are “born alive” Viviparous - internal fertilization and the young obtain nutrients from the mother. Young are “born alive”.