What is the opercula?
in boney fish a protective covering for the gills, it helps control water flow over the gills
Describe the counter current blow flow system and why is it beneficial?
blood in the gills flows in the opposite direction to that of the oxygenated water. It allows for diffusion over a long area
What are denticles?
placoid scales made from the same material as teeth, and are covered with enamel.
What characteristics do Rays have in common?
The are flat,(camouflage, easy movement across the bottom) their mouths are on their ventral side (convenient feeding), eyes are on their dorsal side.
What do fish in the Agnatha class, lack? Can you name 4 structures?
Jaws, also called Jawless fish Also paired fins, scales and true bones
name the sensory organs in a cartilaginous fish and what they sense. (4)
1. Eyes-light, 2.nostrils –smells, 3.lateral line- vibrations in the water, 4 ampulla of Lorenzinii – small electrical currents.
What are chromatophores?
suface pigment cells that expand and contract to create various colors
Name three ways boney fish are different that cartilaginous fish.
1.Swim bladder, 2.terminal mouth, 3.bones, 4.larger scales (cycloid), 5.fins are boney spines covered in a membrane, operculum
Why do bony fish have an Operculum?
it closes while water is let into the gills through the mouth, preventing back flow, ensuring the counter current system of the gills
name the four types of coloration in fishes and what they are used for.
Which lobe of the brain is oversized in a fish?
Olfactory lobe (smelling)
