130 likes | 163 Vues
Learn about the various classes of fish, their characteristics, anatomy, and unique adaptations. Explore how fish breathe, their circulatory system, gill structure, and intriguing adaptations like walking on land. Discover fascinating fish species and their roles in different ecosystems.
E N D
YeshwantraoChavanMahavidyalaya, Tuljapur, Dist.-Osmanabad-413 601 (MH), INDIA Department of Fishery Science Dr S L Bhalkare Head and Assistant prof.
B.Sc. First Year Semester I Paper I Topic: General Chas.of Fishes
Class: Agnatha • Jawless fish • Round, tube-like bodies covered with slimy skin • No scales, bodies made of cartilage • Ex. Lampreys, Hagfish, etc.
Class: Condrichthyes • Cartilaginous fish • Moveable jaws and scales present • Ex. Sharks, Skates and Rays
Class: Osteichthyes • Bony Fish • Skeletons made of hard bone • Scales and a swim bladder present • 95% of ALL fish belong to this class
Pyloriccecum Esophagus Stomach Kidney Brain Swimbladder Vertebra Gills Spinalcord Muscle Mouth Operculum Heart Anus Urinarybladder Reproductiveorgan Pancreas Gallbladder Intestine Liver Anatomy of a Fish
Fish Circulation • Fish have gills that absorb O2 from the water, and release CO2 • Fish have a simple, two-chambered heart
Gill Structure & Function • Gills act as a counter current gas exchanger.
Countercurrent Exchange O2 Concentration
Fish Adaptations • Some fish have remained unchanged for millions of years • Ex. Coelacanth • Some fish are able to “walk” on land, and can survive for long periods of time without water • Ex. Lungfish
Fish Adaptations • Many fish function as a top predator in their ecosystem • Ex. Great Barracuda, Arowana
Fish Adaptations • Many fish are adapted to survive conditions in the deep ocean • lack of sunlight • extreme pressures • Ex. Angler Fish