FISH

Phylum Chordata Vertebrates Animals which have a spinal cord protected by a backbone Fish, amphibians, reptiles, birds & mammals Internal skeletons

The fish Live in water Gills for gas exchange Fins for locomotion Skeleton made of cartilage or bone Most are covered by scales Cold-blooded – body temp. depends on environment

3 classes of fish 1. Jawless fish - agnatha Oldest group – very primitive Scale-less skin Some Parasitic / some filter feed Circular mouth with fleshy teeth Cartilaginous skeleton

Hagfish & lamprey Circular mouth Gill slits

3 classes of fish 2. cartilaginous fish condrichthyes Skeleton made of cartilage Sharks, rays, skates All are predatory except 4 species!

The 4 exceptions are filter feeders Whale sharks – warm shallow water THE LARGEST FISH IN THE SEA!!!

The 4 exceptions are filter feeders Basking sharks – cold shallow water THE SECOND LARGEST FISH IN THE SEA!!!

The 4 exceptions are filter feeders megamouth shark – cold deep water

The 4 exceptions are filter feeders manta ray– shallow warm water

3 classes of fish 3. bony fish - osteichthyes Skeleton of bone Most numerous of fish species Greatest diversity in shape and feeding habits

Body forms of fishes 1. fusiform Sharks, tuna, bluefish Streamlined, torpedo shaped Fast long distance swimmers Open water predators

Body forms of fishes 2. compressed Perch, butterfly fish, angelfish Flattened laterally Quick bursts of speed - short distance Easily move in tight spaces

Body forms of fishes 3. depressed Flounder, fluke, stingray Dorso-ventrally flattened Live on the bottom Eyes on top of body

Body forms of fishes 4. attenuated Eels, lamprey, pipefish Elongated, tubular shape Many Live in holes / burrows Many secrete heavy mucus

Body parts of fish Get ready to draw a fish!!!

1. Caudal fin - tail fin Used for forward motion and acceleration

2. Dorsal fin & 3. Anal fin Singular fins Used to prevent rolling/tipping

4. pectoral fin & 5. pelvic fin paired fins ( left & right) Used to balance, stop & turn

6. Spines Used for protection Some contain poison sacs

7. operculum Covers & protects gills Not found in sharks

8. Lateral line Sensory canals used to detect changes in water pressure around the fish (similar to human ear)

COMPARISON OF CARTILAGINOUS & BONY FISHES TRAIT CARTILAGINOUS BONY_____ EXAMPLES SHARKS, RAYS, SKATES TUNA, COD, SALMON, SKELETON CARTILAGEBONE SWIM BLADDER ABSENT – OILY LIVER PROVIDES BUOYANCY PRESENT – AIR FILLED FOR BUOYANCY

COMPARISON OF CARTILAGINOUS & BONY FISHES TRAIT CARTILAGINOUS BONY_____ FERTILIZATION INTERNAL – HAVE FEW LARGE YOUNG IN LIFE TIME EXTERNAL – LAY MILLIONS OF SMALL EGGS SCALES PLACOID – SPINY EMBEDDED IN SKIN GANOID – PLATELIKE CTENOID & CYCLOID ARE FLAT, FLEXIBLE, OVERLAP

COMPARISON OF CARTILAGINOUS & BONY FISHES TRAIT CARTILAGINOUS BONY_____ GILLSNO OPERCULUM HAVE GILLS SLITS HAVE OPERCULUM COVER & PROTECT GILLS FEEDING BEHAVIOR ALL PREDATORS FOUR EXCEPTIONS GREAT VARIATION IN FOOD SOURCES FINS RIGID AND UNSEGMENTED FLEXIBLE AND SEGMENTED TEETH NOT FUSED TO JAW - REPLACEABLE FUSED TO JAW - IRREPLACEABLE