Where exactly are they?Where exactly are they?

Fish live in either fresh or salt water Fish live in either fresh or salt water (some in anemones), depending on (some in anemones), depending on their specific group. Depending on their their specific group. Depending on their family, they eat anything from small family, they eat anything from small underwater mollusks to other fish.underwater mollusks to other fish.

http://www.nmfs.noaa.gov/habitat/habitahttp://www.nmfs.noaa.gov/habitat/habitatprotection/efh/tprotection/efh/

What is their importance?What is their importance?

Fish do not Fish do not only pay an only pay an important food important food source for humans source for humans and other animals, and other animals, fish also control the fish also control the development of new development of new and old underwater and old underwater life forms. life forms.

How are they unique?How are they unique? Their body structure, Their body structure,

including being a including being a vertebrate or not, is vertebrate or not, is specified for their specified for their lifestyle.lifestyle.

i.e. small, flat fish i.e. small, flat fish typically dwell on the typically dwell on the ocean floors, and ocean floors, and longer fish swim faster longer fish swim faster because of their because of their compressed body compressed body form.form.

Passage of OxygenPassage of Oxygen

Fish use osmosis; Fish use osmosis; oxygen diffuses oxygen diffuses from water to from water to blood and carbon blood and carbon dioxide diffuses dioxide diffuses from blood to from blood to water. water.

Almost all fish Almost all fish breathe with gills. breathe with gills.

The Use of GillsThe Use of Gills

They exchange gases with water. They exchange gases with water. First, the gill slits close, the mouth opens, First, the gill slits close, the mouth opens,

cheeks are pulled sideways, and volume of cheeks are pulled sideways, and volume of the mouth and the pharynx increases. the mouth and the pharynx increases.

That entire process was just water being That entire process was just water being sucked into the fish. sucked into the fish.

The gills slits open, the mouth closes, and The gills slits open, the mouth closes, and the volume decreases. the volume decreases.

That process is water being pushed out of That process is water being pushed out of the slits.the slits.

Skeletal StructureSkeletal Structure

Fish are chordates and they have a Fish are chordates and they have a - notochord (long flexible rod typically - notochord (long flexible rod typically

developed in embryonic stage; developed in embryonic stage; becomes a backbone). becomes a backbone).

- hollow dorsal nerve chord (next to - hollow dorsal nerve chord (next to notochord, main nerve pass notochord, main nerve pass

way way from body to brain)from body to brain) - Pharyngeal slits (slits in the pharynx - Pharyngeal slits (slits in the pharynx

and become featherlike and become featherlike structure for structure for breathing; gills)breathing; gills)

skeleton voice thread

Fish are Vertebrates Fish are Vertebrates Organisms that Organisms that posses a notochord posses a notochord in early in early developmentdevelopment

Replaced by Replaced by stronger support stronger support structure, structure, backbone or backbone or vertebral columnvertebral column

Fish and ReproductionFish and Reproduction

There are two different ways to reproduce as There are two different ways to reproduce as a fish. These two include;a fish. These two include;

- external reproduction- external reproduction - used by most fish.- used by most fish. - the male deposits sperm into the - the male deposits sperm into the

water and water and the female deposits the egg into the female deposits the egg into the water. the water. - fertilization occurs and the egg is - fertilization occurs and the egg is hatched.hatched.

- Ovoviviparous reproduction.- Ovoviviparous reproduction. - used by some sharks and bony fish.- used by some sharks and bony fish. - Eggs are retained in female until - Eggs are retained in female until

hatched, hatched, and embryos get their food from and embryos get their food from the yolk the yolk sac. sac.

Nervous SystemNervous SystemFishes’ nervous system is set up similar to Fishes’ nervous system is set up similar to

the human’s, except it is simpler. the human’s, except it is simpler. There are five parts to their nervous There are five parts to their nervous

system;system; - Olfactory Bulbs- Olfactory Bulbs - Cerebrum - Cerebrum - Optic Lobes- Optic Lobes - Cerebellum - Cerebellum - Medulla Oblongata- Medulla Oblongata

Nervous System cont.Nervous System cont.

Olfactory bulbsOlfactory bulbs

CerebrumCerebrum

Optic lobesOptic lobes

CerebellumCerebellum

Medulla OblongataMedulla Oblongata

-sense of smell.-sense of smell.

-basic behaviors.-basic behaviors.

-visual info.-visual info.

-body movement.-body movement.

-to maintain balance. -to maintain balance.

Sensory StructuresSensory Structures Chemical receptors are Chemical receptors are

a good example of a good example of sensory structures; sensory structures; these are “smelling these are “smelling with lips and tasting with lips and tasting with barbels [whiskers].”with barbels [whiskers].”

Specialized cells which Specialized cells which detect tiny electric detect tiny electric currents to find hidden currents to find hidden prey.prey.

Some fish with Some fish with specialized cells use specialized cells use them to navigate and them to navigate and communicate. communicate.

Fish Lateral Line SystemFish Lateral Line System

• The system is sensitive to changing The system is sensitive to changing water pressures.water pressures.

• The sensory unit is called “neuromast”The sensory unit is called “neuromast”– A bundle of sensory cells that hairs are included in a A bundle of sensory cells that hairs are included in a

jelly-like cap. jelly-like cap. – It sends out nerve impulses through out the fish’s It sends out nerve impulses through out the fish’s

body.body.

• When pressure waves bend with the When pressure waves bend with the body, it determines the frequency of body, it determines the frequency of nerve impulses.nerve impulses.

Circulatory SystemCirculatory System

Single-looped Single-looped system with two system with two chamber heart. chamber heart.

This includes the This includes the atrium and ventricle.atrium and ventricle.

Heart is near the Heart is near the respiratory organs. respiratory organs.

Blood travels first to Blood travels first to gills then rest of gills then rest of body. body.

Excretory SystemExcretory System

Many fish rid of waste by Many fish rid of waste by allowing ammonia to allowing ammonia to diffuse through gills. diffuse through gills.

Simple kidney filters waste Simple kidney filters waste from blood, and also pass from blood, and also pass dilute urine.dilute urine.

Gills’ specialized cells can Gills’ specialized cells can pump salts in/out of body pump salts in/out of body fluids. fluids.

The Swim Bladder The Swim Bladder

• Is a flexible-walled Is a flexible-walled organ near the dorsal organ near the dorsal fin of dorsal fin.fin of dorsal fin.

• Controls the fishes’ Controls the fishes’ buoyancy in the water.buoyancy in the water.

• Depends of the amount Depends of the amount of pressure in the fish.of pressure in the fish.

– i.e. if the fish becomes i.e. if the fish becomes positively buoyant, it positively buoyant, it floats to the top and floats to the top and the gases escape from the gases escape from the swim bladder.the swim bladder.

Digestive SystemDigestive System Is complete, with Is complete, with

similar organs as similar organs as humans have:humans have: StomachStomach Small intestinesSmall intestines Large intestinesLarge intestines

ClassesClasses

There are three major fish classes. These There are three major fish classes. These include:include:

- Agnatha- Agnatha - Chondrichthyes- Chondrichthyes - Osteichthyes - Osteichthyes

http://www.geocities.com/aquarium_fish/fishclasses.hthttp://www.geocities.com/aquarium_fish/fishclasses.htmm

Agnatha ClassAgnatha Class

Primitive jawless Primitive jawless fish.fish.

They have lost their They have lost their bony skeletons.bony skeletons.

They have no scales.They have no scales. Examples: lampreys Examples: lampreys

and hagfish.and hagfish.

ChondrichthyesChondrichthyes Fish with a jaw.Fish with a jaw. Cartilaginous Cartilaginous

skeletons.skeletons. Includes sharks, Includes sharks,

rays, and skates. rays, and skates. Plate-like scales.Plate-like scales. There are 750 There are 750

living species left.living species left. Most are Most are

carnivores.carnivores.

OsteichthyesOsteichthyes These are bony fish.These are bony fish. Skeletons made of strong, Skeletons made of strong,

lightweight bone.lightweight bone. There are 30,000 species.There are 30,000 species. Biologists divide them into two Biologists divide them into two

subclasses; subclasses; Ray-finned fishes.Ray-finned fishes. Fleshy-finned fishes (includes lobe-Fleshy-finned fishes (includes lobe-

finned and lungfishes). finned and lungfishes).

Osteichthyes: Ray-finned Osteichthyes: Ray-finned FishesFishes

Includes nearly all Includes nearly all of the bony fishes.of the bony fishes.

Many perform Many perform feats that you feats that you wouldn’t imagine.wouldn’t imagine.

Includes: guppies, Includes: guppies, groupers, blue fish, groupers, blue fish, flounders, flounders, anchovies, eels, anchovies, eels, salmon, and more. salmon, and more.

Above is a flying fish

Osteichthyes: Fleshy-finned Osteichthyes: Fleshy-finned FishesFishes

Lobe-finned fishes.Lobe-finned fishes. - Today, the only living species - Today, the only living species

is is the Latimeria (also the Latimeria (also known as known as Coelacanth). Coelacanth). - These fish live in deep sea. - These fish live in deep sea. - These are closest to the - These are closest to the

common common ancestor of all four-limbed ancestor of all four-limbed vertebrates. vertebrates.

Latimeria CoelacanthLatimeria Coelacanth

Replica of most famous Latimeria

Visit: http://nature.ca/discover/treasures/anim/tr3/coe_e.cfm orhttp://sacoast.uwc.ac.za/education/resources/fishyfacts/coelacanth.htm

Fleshy-finned FishFleshy-finned Fish LungfishLungfish

They have They have retained their retained their primitive lung.primitive lung.

Is an air-filled sac Is an air-filled sac connected to the connected to the gut. gut.

Fills its lung by Fills its lung by swallowing air and swallowing air and empties by empties by belching. belching.

The End!The End!

Works Cited (pictures)Works Cited (pictures)• National GeographicNational Geographic. 2008. National Geographic . 2008. National Geographic

Society. Society. 31 March 2008. 31 March 2008. <http://animals.nationalgeographic.com/staticfiles/<http://animals.nationalgeographic.com/staticfiles/NN GS/Shared/StaticFiles/animals/images/GS/Shared/StaticFiles/animals/images/primary/parroprimary/parro t-fish.jpg>.t-fish.jpg>.

• College of SciencesCollege of Sciences. 2008. San Diego State . 2008. San Diego State University. 2 University. 2 April 2008. April 2008. <http://www.sci.sdsu.edu/classes/bio100/Lectures/<http://www.sci.sdsu.edu/classes/bio100/Lectures/LeLe ct16/Image266.gif>.ct16/Image266.gif>.

• Kimball, John W. “Kimball's Biology Pages.” Kimball, John W. “Kimball's Biology Pages.” Biology Biology PagesPages. 14 March 2008. 3 April 2008. . 14 March 2008. 3 April 2008.

<http://users.rcn.com/jkimball.ma.ultranet/Biology<http://users.rcn.com/jkimball.ma.ultranet/BiologyPaPa ges/F/fish_heart.gif>.ges/F/fish_heart.gif>.

• University of AberdeenUniversity of Aberdeen. 20 March 2008. King’s . 20 March 2008. King’s College. 3 College. 3 April 2008. <April 2008. <http://www.abdn.ac.uk/

~nhi708/images/coelacanth.jpg>.

Works Cited (pictures)Works Cited (pictures)• ““Archives.” Archives.” Tomorrow Yesterday!Tomorrow Yesterday! 2008. 2 April 2008. 2008. 2 April 2008.

<http://www.tomorrowyesterday.com/archives/nemo.<http://www.tomorrowyesterday.com/archives/nemo.jj pg>.pg>.

• ““Fish Biology.” Fish Biology.” National Aquarium of New ZealandNational Aquarium of New Zealand. . 2008. 2008. National Aquarium of New Zealand. 1 National Aquarium of New Zealand. 1 April 2008. April 2008. <http://www.nationalaquarium.co.nz/docs/<http://www.nationalaquarium.co.nz/docs/

programmes/Fishbiol.pdf>.programmes/Fishbiol.pdf>.• ““Fish.” Fish.” Sportsman ChoiceSportsman Choice. 27 Feb 2008. 3 April 2008. . 27 Feb 2008. 3 April 2008.

<http://www.sportsmanschoice.com/A%20Note<http://www.sportsmanschoice.com/A%20Note%20%20 Worth%20Reading/encyclopedia/lr000531.gif>.Worth%20Reading/encyclopedia/lr000531.gif>.

• ““Latimeria Coelacanth.” Latimeria Coelacanth.” PALAEOS: The Trace of Life PALAEOS: The Trace of Life on on EarthEarth. . 2008. 3 April 20082008. 3 April 2008.. <<http://www.palaeos.com/Vertebrates/Units/http://www.palaeos.com/Vertebrates/Units/140Sarcopterygii/Images/LatimeriaPhoto.jpg>.140Sarcopterygii/Images/LatimeriaPhoto.jpg>.

• ““Latimeria.” Latimeria.” Practical FishkeepingPractical Fishkeeping. 2008. 4 April . 2008. 4 April 2008. 2008. <http://www.practicalfishkeeping.co.uk/pfk/images/<http://www.practicalfishkeeping.co.uk/pfk/images/

latimeria_chalumnae_cc.jpg>.latimeria_chalumnae_cc.jpg>.

Works Cited (websites)Works Cited (websites)• “Modern Coelacanth.” Our Amazing Treasures. 22 June

2006. Canadian Museum of Nature. 4 April 2008. <http://nature.ca/discover/treasures/anim/tr3/coe_e.cfm>.

• “The Coelacanth.” Coastcare: South African Coastal Information Centre. 2008. Department of Environmental Affairs and Tourism. 4 April 2008. <<http://sacoast.uwc.ac.za/education/resources/fishyfacts/coelacanth.htm>.

• ““Fish Classes.” Fish Classes.” Hand MadeHand Made. 3 March 2006. 2 April . 3 March 2006. 2 April 2008. 2008. <http://www.geocities.com/aquarium_fish/<http://www.geocities.com/aquarium_fish/

fishclasses.htm>.fishclasses.htm>.• ““Essential Fish Habitat.” Essential Fish Habitat.” Habitat Protection DivisionHabitat Protection Division. .

NOAA Fisheries. 3 April 2008. NOAA Fisheries. 3 April 2008. <http://www.nmfs.noaa.gov/habitat/<http://www.nmfs.noaa.gov/habitat/

habitatprotection/efh/>.habitatprotection/efh/>.

Works Cited (websites) cont.Works Cited (websites) cont.

““Fish Lateral Line System”. Fish Lateral Line System”. Lateral Lateral System. System. 8 April 2008. 8 April 2008. http://www.lookd.com/fish/laterallinehttp://www.lookd.com/fish/laterallinesystem.htmlsystem.html

Works Cited (books)Works Cited (books)

• Filisky, Michael. Filisky, Michael. Peterson First Peterson First Guides: Guides: FishesFishes. Boston, Mass: . Boston, Mass: Houghton Mifflin Houghton Mifflin Company, 1989.Company, 1989.

• Miller, Kenneth and Levine, Joseph. Miller, Kenneth and Levine, Joseph. Biology: The Living ScienceBiology: The Living Science. Upper . Upper Saddle River, NJ: Prentice-Hall, 1998.Saddle River, NJ: Prentice-Hall, 1998.

Works Cited (videos)Works Cited (videos)

• ““Videos.” Videos.” Discovery Education Discovery Education StreamingStreaming. . 2008. Discovery 2008. Discovery Communications, LLC. 2 Communications, LLC. 2 April April 2008.<http://streaming.discovery 2008.<http://streaming.discovery

education.education.com>.com>.