Special organs that allow oxygen and carbon dioxide to pass between the water and the fish's blood.
Curved arch of cartilage from which branch two rows of long, narrow gill filaments
Long and narrow, Looks like a stack of thin disks connected by a narrow stalk containing blood vessels.
Beneath the operculum. Opens into the fish's pharynx.
A wide plate of bone that protects the gills. Found on each side of the head.
Vanelike projections from the front of each gill arch that strain food particles and other debris out of the water.
How many chambers does a fish's heart have?
A fish's mouth, the beginning of the fish's digestive system.
Jaws of a fish are often lined with various types of these. These are designed to suit the fish's diet.
A fish's throat. Separated from the gill cavities by a screen of gill rakers
A short, straight tube that leads to a fish's stomach.
Located low in the fish, near the center of the body cavity. It primarily digests food.
A fish senses faint vibrations and pressure changes in the water by means of this. It is a system of special nerve endings that extends over its head and sides of its body.
Cells are released through this to reproduce. Located slightly to the rear of the anus.
Lay their eggs
A fluid released by the male to fertilize the eggs
A hollow gas-filled chamber located high in the fish's body cavity. Allows the fish to adjust its buoyancy.
Located in the wall of the bladder. It extracts oxygen and other gasses from the fish's blood and uses the gas to inflate the swim bladder.