Ashley ELsa & Vivian Fish Body Systems

Fish Body Systems

Reproduction

Nervous System

• The fish reproductive system is simkple and both sexes are usually seperate.
• Cartiliaginous fish have ducts which lead from the ovaries and testes into the cloaca.
• Jawless and bony fish have a seperate opening for urine and gametes called the urogenital opening, located behind the anus.
• The timing of reproduction is controlled by sex hormones, these hormones are produced in the gonads and released into the blood.
• Some fish are hermaphrodites and can fertilize their own eggs this ism ore common in deep water fish.
• A variation of hermaphroditism is sex reversal, which is when a fish begins its life as a male and change into females or vice versa.

Respitory System

Circulatory System

Coloration

• All fishes have a two-chambered heart located below the gills.
• After blood is pumped gas exchange takes place.
• Blood is carried to the body by arteries.
• Arteries branch out into capillaries, that allow oxygen and nutrients to reach every cell.
• Capillaries collect into larger blood vessels called veins which carry deoxygenated blood and dissovle carbon dioxide back to the heart to complete the cycle.

• Verterbrates have the most complex and advanced nervous systems of any animal group.
• At the heart of the system is the central nervous, consisting of the brain and spinal cord.
• Most fishes have a highly developed sense of smell, which they use to detect food, mates, and predators and somestimes to find their way home.
• Fishes detect other chemical stimuli with taste buds located in the mouth and on the lips, fins and skin.
• Fishes have a unique sense organ called the lateral line that enables them to detect vibrations in the water.
• Cartilaginous fishes also have sense organs in the head called the ampullae of Lorenzini that can detect weak electrical fields.
• Many fishes detect changes in body position from movement of calcareous ear stones, or otliths, that rest on sensory hairs, a mechanism similar to the statocysts of invertebartes.

• Bony fish use color for camouflage.
• Fishes have structural colors that result

when a special surface reflects only certain

colors of light.

• Some fish change color with the mood or

reproductive condition.

• Obtain oxyegn dissolved in water and release carbon dioxide from their blood through paired gills.
• Fishes get the oxygen they need by extracting it from water.
• When sharks swim opening and closing of the mouth forces water through the mouth, over the gills, and out through gill slits.
• Fish gills are supported by cartilaginous or bony structures, the gill arches.
• Each gill arch bears two rows of slender fleshy projections called gill filaments.
• Oxygen dissolved in the water diffuses into the capillaries of the gill filaments to oxygenate the blood.
• Once oxyegn enters the blood its carried through the body by hemoglobin, a red protein that gives blood its charactersitic color.

Locomotion

• A rhythmic swimming motion

of a fish body or scale.

• Fishes swim to obtain food

and escape predators.

• Rhythmic contractions are produced by

bands of muscle called myomeres.

• Myomeres run along the side of the body.

Regulation of the Internal

Environment

Feeding

Digestion

Behavior

• Most sharks are carnivores.
• some fish are filter feeders, which means

that they feed by filtering tiny organisms or fine

particles of organic material.

• mantas feed on plankton and small fish.

bony fish hav protrusible jaws, that allow

more flexibility in their feeding habits.

• most bony fish are carnivores.

• In contrast to most marine organisms, the blood of marine bony fishes is less salty than seawater.
• Marine bony fishes therefore need to osmoregulater to prevent dehydration.
• To replace lost water, they swallow seawater.
• Salts are absorbes and excreted by the kidneys, the most important excretory organs of veretbrates, and specialized chloride cells in the gills.
• Cartilaginous fishes also absorb water to prevent dehydration, mostly through the gills and from food.
• Excess salts are excreted by the kidneys, intestine, and a special gland near the anus called the rectal gland.

• After food is swallowed, it

passes through the pharynx, then

the esophagus and into the stomach.

• The stomach is where digestion begins.
• Food passes from the stomach into the intestine
• Intenstines secrete digestive enzymes.
• The liver secretes bile needed yo break down fats.
• Fishes like cartilaginous and primitive bony contain a spiral portion called the spiral valve.

• Important part of fish courtship and reproduction, which are described in the next section.
• Many marine fishes, particularly open-water species, do not reside in any particular area.
• Fishes establish territories, home areas that they defend against intruders.
• Fishes use a variety of aggresive behaviors to defend their territories.
• Fish avoid risking injury by bluffing, and raise fins open their mouths or dart rapidly as a threat to other fish.

Body Shape

• Directly related to it's lifestyle.
• Fast swimmers have a streamline body shape.
• Laterly compressed bodies are good for leisure swimming.
• These types of bodies allow for bursts of speed to escape from enemies or capture food.