| A | B |
|---|
| vertebral column | the vertebrae or the spine |
| cranium | skull |
| Lampreys and Hagfishes | class Agnatha, fish with elongated eel like bodies, they lack jaws, paired fins and bone |
| Sharks, Rays, and Skates | class Chondrichthyes, predatory fish with jaws and paired fins, their skeletons are made of cartilage, not bone, and their skin is covered by a unique scale |
| Bony Fish | class Osteichthyes, guppies, salmon, bass, catfish, all have jaws, and most have a skeleton composed of bone |
| Amphibians | class Amphibia, frogs, toads, and salamanders, all have thin skin permeable by gases and water, they lay their eggs in water and pass through an aquatic larval stage |
| Reptiles | class Reptilia, turtles, crocodiles, alligators, lizards, and snakes, skin is dry and scaly, eggs are laid on land |
| Birds | class Aves, adaptations that enable flight, including feathers, hollow bones, and a unique respiratory system |
| Mammals | call Mammalia, humans, cats, mice, and horses to name a few, all have hair and nurse their young |
| gill arches | skeletal elements that support the pharynx |
| lateral line system | consists of a row of sensory structures that run the length of the fish's body on each side and that are connected by nerves to the brain |
| external fertilization | fertilization occurs outside the body of either parent |
| cartilage | flexible lightweight material made of cells surrounded by tough fibers of protein |
| placoid scales | small, toothlike spines that feel like sandpaper that cover the skin of cartilaginous fishes |
| pectoral fins | found behind a shark's head jutting out of the body like wings of a plane |
| olfactory bulbs | paired nostrils on the snoaut have specialized nerve cells that connect these, where the information from the nostrils is analyzed |
| rectal gland | located in the posterior portion of the intestine, removes excess sodium and chloride ions from the blood and releases them into the rectum for elimination |
| internal fertilization | fertilization occurs inside the body of the female |
| claspers | during mating the male transfers sperm into the female's body with modified pelvic fins |
| bone | material typically harder and heavier than cartilage, the skeletons of most body fishes contain bone |
| lungs | internal respiratory organs in which gas is exchanged between the air and blood |
| swim bladder | a gas-filled sac that is used to control buoyancy |
| scales | the body of a bony fish is usually covered with scales, scales protect the fish and help reduce water resistance |
| lobe-finned fishes | have fleshy fins that are supported by a series of bones |
| ray-finned fishes | have fins that are supported by long, segmented, flexible bony elements called rays |
| operculum | a hard plate that opens at the rear and covers and protects the gills |
| caudal fin | extends from the tail and moves from side to side and amplifies the swimming motion of the body |
| dorsal fins | 2 of them one anterior and one posterior help keep the fish upright and moving in a straight line |
| anal fin | help keep the fish upright and moving in a straight line |
| pelvic fins | 2 fins used with the pectoral fins to navigate, stop, and move up and down and even back up |
| pectoral girdle | the attachment point for the pectoral fins |
| pelvic girdle | attachment point for the pelvic fins |
| esophagus | food moves from here to the stomach |
| stomach | secretes acid and digestive enzymes that break down the food |
| intestine | food passes into here wher digestion is completed and nutrients are absorbed |
| liver | located near the stomach and secretes bile |
| bile | helps break down fats |
| gallbladder | stores bile and releases it into the intestine |
| pancreas | also located near the stomach releases digestive enzymes into the intestine |
| anus | undigested material is eliminated through here |
| arteries | heart pumps blood through here to small thin walled vessels |
| capillaries | small thin walled vessels where the blood picks up oxygen and releases carbon dioxide |
| veins | the blood returns to the heart through these |
| sinus venosus | deoxygenated blood from the body empties into this collecting chamber |
| artium | from the sinus venosus the blood moves into here |
| ventricle | contraction of the atrium speeds up the blood and drives it into here |
| conus arteriosus | this is the final chamber , it has an elastic wall and usually contains valves to prvent blood flow from flowing back into the ventricle |
| countercurrent flow | water flows away from the head while blood flows toward the head, this allows more oxygen to diffuse into the gills than would be possible if blood and water flowed in the same direction |
| urine | kidney's filter dissolved chemical wastes from the blood resulting in this solution |
| urinary bladder | where urine is stored and later expelled |
| cranial nerves | the major sensory organs are connected directly with the brain via these |
| cerebrum | this area of the forebrain has areas that integrate sensory and other types of information form other area of the brain |
| optic tectum | dominates the midbrain and receives and processes information from the fish's visual, auditory, and lateral line systems |
| cerebellum | this part of the brain is in the hindbrain and helps coordinate motor output |
| medulla oblongata | located in the hindbrain and helps to control some body functions and acts as a relay station for stimuli from sensory receptors throughout the fish's body |
| spinal nerves | connect the spinal cord with the internal organs, muscles, and sense organs |
| spawning | reproductive behavior |
