Osteichthyes (bony fishes) Костные рыбы Лекция № 6

SYSTEMATICS Kingdom: Animals Type: Chordates Superclass: Osteichthyes (bony fishes) This superclass contains of: Class Actinopterygii (ray-finned fishes) Лучеперые Class Sarcopterygii (lobe-finned fishes) Лопастеперые

Contents Anatomy Derma Skeleton Digestive system Breathing system Circulatory system Nervous system The senses (+SWIM BLADDER) Reproductive system Excretory system

Anatomy

Derma Scale : Ganoid scales Cosmoid scales Cycloid scales

Skeleton Have bony, as opposed to cartilaginous, skeletons.. 1)Axial skeleton: Vertebral column Cerebral part of the skull 2)Visceral skeleton

Digestive system At the end of the stomach, many bony fishes have blind sacs called pyloric caeca. The pyloric caeca are an adaptation for increasing the gut area; they digest food.  The pancreas secretes enzymes into the intestine for digestion.

Breathing system Water enters the gill chamber through a fish's mouth and exits through gill openings under the operculum. Blood flowing through the gill filaments absorbs oxygen from the water.

Circulatory system A bony fish's heart has two chambers: an atrium and a ventricle. The venous side of the heart is preceded by an enlarged chamber called the sinus venosus. The arterial side of the heart is followed by a thickened muscular cavity called the bulbus arteriosus

Nervous system 5 sections: front, middle, intermediate, elongated, and the cerebellum + 10 pairs of cranial nerves

The senses (+SWIM BLADDER): Bony fishes have a basic vertebrate eye, with various structural adaptations. A bony fish's eye includes rods and cones. The ears of a bony fish function in equilibrium, detecting acceleration, and hearing. Lateral line. Bony fishes have taste buds in their mouths. Some species have taste buds along the head and ventral side of the body. Olfactory cells in the nasal sac detect tiny amounts of chemicals in solution. Плавательный пузырь Apparently the swim bladder originally developed in fish as an organ of respiration, as evidenced by the "lung" of the lungfishes.

Reproductive system In most species of bony fishes, sperm and eggs develop in separate male and female individuals. Males and females may look similar, or they may look very different. Male/female differences may include size, coloration, external reproductive organs, head characteristics, and body shape.

Excretory system