Characteristics:

• 1) skeleton made up of bone

• 2) lungs (early bony fish) or swim bladder present

• 3) scales –cover body: protection and reduce water resistance

Yellow Perch

eel

Two-main groups: • I -Lobe-finned –fleshy fins supported with a

series of bones (Most are extinct). Most are lungfish. One species called the coelacanth is a lobe-finned fish, thought to be extinct, but found to exist in modern times. Extinct lobe-finned fish are thought to be ancestors to amphibians.

• coelacanth – found off the coast of South Africa in 1938,(5 feet long). Since then, there have been many caught off the coast of Madagascar & Mozambique.

II -Ray-finned – fins with long segmented bony elements and no central bone support.

Yellow Perch

large mouth bass

Characteristics

• 2) operculum: hard plate over gills

• 3) scales: overlapping, bone-like disks grow from pockets in skin

king salmon scales

5) Complete digestive system

• 6) Circulatory system: • A fish heart has one atrium and one ventricle,

so you may think of it as a two-chambered heart. Heart pumps blood to arteries, to capillaries (in the gills where gas exchange takes place), to veins, to the heart.

FISH HEART

Blood Flow

• 7) Fish kidneys filter chemical waste from the blood. Urine is stored in the urinary bladder_, & later expelled. By varying the amount of water and salts in the urine, the kidneys help regulate the water and ion balance. The gills also regulate the concentration of ions in the body.

• 8) Swim bladder : Fish adjust their overall density and thus their vertical position in the water through the gas in the swim bladder. This bladder is like a long balloon and is connected to the fish's bloodstream through tiny blood vessels called capillaries.

• The oxygen and other gases that the fish gets from the water through its gills can go back and forth from the blood to the bladder and from the bladder to the blood. When the fish needs to dive, the bladder gives up some gas to the blood and deflates a little. This makes the fish a little more dense so its easier to go down. When the fish needs to go toward the surface, the blood gives gas to the bladder causing it to inflate. This makes the fish less dense so it is easier

• 9) Brain, spinal cord, and various sensory organs make up the nervous system. Sensory organs are connected to the brain by the cranial nerves.

• 10) Reproduction through spawning: eggs and sperm released in the water. Some fish bear live young (ovoviviparous) --(Some nest-building)

• Albino ratfish • Green-eyed and almost purely white, the albino ratfish's

front teeth look similar to those of a rodent. It appears shiny thanks to a crystalline layer right under the surface of its skin.

• But the eye-catching creature usually gets eaten by predators -- before being able to pass on its mutant genes, which stop the production of skin pigment. Scientists discovered this albino anomaly in summer 2007 off Whidbey Island, Wash.

A deep-sea Angler fish

Hawaii’s Round Belly Cowfish

JAPANESE SUNFISH

• Some Fish that washed up after the South- East Asia Tsunami of 2005.

Goldfish Facts

Goldfish are tasty!

May Be the Largest Goldfish

Puffer Fish of “Blowfish”

The Story of Fugu – Edible, Poisonous Puffer Fish

• Fugu (blow fish) is a fish which contains deadly poison in the organs. Despite the risk, fugu dishes remain as special feasts in Japan. Even the milt is considered as a great delicacy. Fugu is referred to as blow/globe/puffer fish since it blows its body up.

• It's reported that about 40 kinds of blow fish are caught and cultured in Japan and that 10000 tons of blow fish are consumed each year. Shimonoseki-city in Yamaguchi, is known as fugu city and supplies a large amount of fugu.

• There is an old expression such that "I want to eat fugu, but I don't want to die" in Japan. Since fugu's poison can lead to instantaneous deaths of diners, only licensed cooks are allowed to prepare fugu. You must have special skills and knowledge about fugu to be licensed. Poisonous parts of fugu differ, depending on the kind of fugu. Because of the strict regulations, the number of deaths is decreasing.

• Fugu dishes are usually expensive. One meal can cost $100 to $200 per person at a famous restaurant. But there are inexpensive fugu dishes (from $15 to $20) available at some restaurants. It's said that the most poisonous fugu, "Tora-fugu," is the most delicious. Tora-fugu is expensive and can cost over one hundred dollars at a fish market. Nowadays, prepared-fugu are sold at grocery stores and online stores, and fugu are eaten at Japanese homes.

Homer Simpson eating fugu

Expensive restaurant fugu

fugu at the fish market