0790-0791 uo9 bdol-829900 8/4/04 4:21 pm page 790 ... enable them to “fly” over the ocean bottom...
TRANSCRIPT
VertebratesWhat Yoursquoll LearnChapter 30
Fishes and Amphibians
Chapter 31 Reptiles and Birds
Chapter 32 Mammals
Chapter 33 Animal Behavior
Unit 9 ReviewBioDigest amp Standardized Test Practice
Why Itrsquos ImportantAnimals classified as vertebrates have an internal skeletonand a backbone These features along with the develop-ment of lungs and in most vertebrates limbs haveallowed them to make the transition from life in water tolife on land with great success
1671A torpedo fish a type ofelectric ray is dissectedThe electric organ isexamined but scientistsremain unaware that it produces electricity
Understanding the PhotoVertebrate animals have structural and physiologicaladaptations that allow them to live in all of Earthrsquosbiomes including arctic waters deserts rain forestsand mountain plateaus Guanacosmdashrelatives ofcamels llamas alpacas and vicuntildeasmdashinhabit areasof Peru Chile and Argentina including the Andes at altitudes up to about 4000 m
1735Carolus Linnaeuspresents a sys-tem for classify-ing organismsbased on struc-tural similarities
790
1680The first clocks withhands to indicateminutes are designed
Torpedo fish
cabdolglencoecomwebquest(tl)Mark SmithPhoto Researchers (tr)Historical Pictures Service Chicago (crossover)Howie GarberAnimals AnimalsEarth Scenes
0790-0791 UO9 BDOL-829900 8404 421 PM Page 790
1977A woollymammoth isfound pre-served in icein the SovietUnion
2002Scientistsannounce the dis-covery of two newspecies of mon-keys and a newspecies of parrotin the Amazonrain forest
1845The firstinflatable rubbertire is invented
1969Neil Armstrongwalks on themoon
791
1836The first livingspecies of lungfishis discovered inSouth America
Okapi
1901Despite its zebra-like markings theokapi is correctlyidentified as a rela-tive of the giraffe
Ken Lucas PhotoVisuals Unlimited
0790-0791 UO9 BDOL-829900 8404 425 PM Page 791
Fishes and AmphibiansFishes and
Amphibians
Understandingthe Photo
792
Visit tobull study the entire chapter
onlinebull access Web Links for more
information and activities onfishes and amphibians
bull review content with theInteractive Tutor and self-check quizzes
Fred BavendamAnimals Animals
Seahorses are bony fishes Theyswim upright and slowly moveforward An adaptation thatallows them to capture prey istheir long snout It functions likea suction to draw in small organ-isms that pass by in the waterSeahorse species range in sizefrom about 4 cm to 20 cm
What Yoursquoll Learn You will compare and contrast
the adaptations of the differ-ent groups of fishes andamphibians
You will learn about the origin of modern fishes andamphibians
Why Itrsquos ImportantFishes are the most diverse verte-brate group Amphibians areadapted to live both in water andon land The development of abony endoskeleton in fishes andlungs in amphibians were majorsteps in animal evolution
cabdolglencoecom
0792 C30Open BDOL-829900 8404 1107 PM Page 792
Fishes301
What is a fishFishes like all vertebrates are classified in the phylum Chordata This
phylum includes three subphyla Urochordata the tunicates Cephalo-chordata the lancelets and Vertebrata the vertebrates Fishes belong tothe subphylum Vertebrata In addition to fishes subphylum Vertebrataincludes amphibians reptiles birds and mammals Recall from the pre-vious chapter that all chordates have four traits in commonmdasha noto-chord pharyngeal pouches postanal tail and a dorsal hollow nerve cordIn vertebrates the embryorsquos notochord is replaced by a backbone in adultanimals All vertebrates are bilaterally symmetrical coelomates that haveendoskeletons closed circulatory systems nervous systems with complexbrains and sense organs and efficient respiratory systems
Classes of fishesFishes can be grouped into four classes of the subphylum Vertebrata The
jawless fishes belong to the superclass Agnatha which means ldquowithout jawsrdquoSuperclass Agnatha consists of two classes class Myxini (mik SEE nee) hag-fishes and class Cephalaspidomorphi (se fa LAS pe do MOR fee) lampreys
SECTION PREVIEWObjectivesRelate the structuraladaptations of fishes to their environmentsCompare and contrastthe characteristics of thedifferent groups of fishesInterpret the phylogenyof fishes
Review Vocabularyvertebrate an animal with
a backbone (p 685)
New Vocabularyspawningfinlateral line systemscaleswim bladdercartilage
Answer Questions As you read Chapter 30 answer the question and fill in information about fishes behind the tabs
Fishes Make the following Foldable to help you organize information about the diversity and originsof fishes
Fold a sheet of paper in half lengthwise Make the back edge about 2 cm longer than the front edge
Turn the paper so the fold is on the bottom Then fold it into thirds
Unfold and cut only the top layer along both folds to make three tabs
Label the Foldable as shown
STEP 1
STEP 3
STEP 2
STEP 4
Fishes
What isa fish
Originof Fishes
Diversityof Fishes
301 FISHES 793
0793-0802 C30S1 BDOL-829900 8404 957 PM Page 793
BDOL-301
null
72793134
Class Chondrichthyes (kahn DRIHK
theez) is comprised of cartilaginousfishes such as sharks and rays andclass Osteichthyes (ahs tee IHK theez)contains the bony fishes Examplesfrom the different classes are shownin Figure 301
Fishes inhabit nearly every type of aquatic environment on EarthThey are found in freshwater and salt water and adapted to living in shallowwarm water and deeper cold andlightless water
Fishes breathe using gillsFishes have gills made up of feathery
gill filaments that contain tiny bloodvessels Gills are an important adapta-tion for fishes and other vertebratesthat live in water As a fish takes waterin through its mouth water passes overthe gills and then out through slits atthe side of the fish Oxygen and carbondioxide are exchanged through the cap-illaries in the gill filaments You canfind out more about the structure andfunction of gills in fishes in theMiniLab on the next page
Fishes have two-chambered hearts
All fishes have two-chamberedhearts as shown in Figure 302 Onechamber receives deoxygenated bloodfrom the body tissues and the secondchamber pumps blood directly to thecapillaries of the gills where oxygenis picked up and carbon dioxidereleased Oxygenated blood is carriedfrom the gills to body tissues Bloodflow through the body of a fish is rel-atively slow because most of theheartrsquos pumping action is used to pushblood through the gills
Fishes reproduce sexuallyAlthough the method may vary all
fishes reproduce sexually Fertiliza-tion and development is external inmost fishes Eggs and sperm can bereleased directly into the water ordeposited in more protected areassuch as on floating aquatic plantsAlthough most fishes produce largenumbers of eggs at one time hagfishes produce small numbers ofrelatively large eggs
794 FISHES AND AMPHIBIANS(bl)Breck P KentAnimals Animals (bc)Andrew J MartinezPhoto Researchers (br)Jeremy Stafford-DeitschENP Images
Figure 301Examples of fishes include jawlessfishes cartilaginous fishes andbony fishes
Jawless fishes called lampreys havelong tubular bodies without scalesand paired fins
A
Cartilaginous fishes calledskates have a flattened bodyshape with large paired finsthat enable them to ldquoflyrdquoover the ocean bottom asthey search for food
C
Most fishes you are familiarwith are bony fishes suchas this swordfish
B
0793-0802 C30S1 BDOL-829900 8404 958 PM Page 794
301 FISHES 795
Cartilaginous fishes have internalfertilization Skates deposit fertilizedeggs on the ocean floor Some femalesharks and rays carry developingyoung inside their bodies Becausethese young fishes are well developedwhen they are born they have anincreased chance of survival
Most bony fishes have external fertilization and development Thistype of external reproduction in fishesand some other animals is calledspawning During spawning somefemale bony fishes such as cod pro-duce as many as 9 million eggs ofwhich only a small percentage surviveIn some bony fishes such as guppiesand mollies fertilization and develop-ment is internal Most fishes that pro-duce millions of eggs provide no carefor their offspring after spawning Inthese species only a few of the youngsurvive to adulthood Some fishes suchas the mouth-brooding cichlids staywith their young after they hatchWhen their young are threatened bypredators the parent fishes scoop theminto their mouths for protection
Summarize the different reproductive methods ofcartilaginous and bony fishes
Aorta
Heart
GillsCapillarynetwork
Figure 302Blood in a fish flows in a one-way circuitthroughout the body
Observe and InferStructure and Function of Fishesrsquo Gills Fishes remove oxy-gen from the water by means of gills Water enters a fishrsquosmouth moves over the gills and out through openings on thesides of the head The gills are made up of thin filaments con-taining blood vessels Inside the gills blood moves in theopposite direction to the flow of water When blood andwater flow in opposite directions the oxygen concentrationdifference between the water and the blood is large enoughfor oxygen to diffuse from water into blood
Procedure Examine a prepared slide of a fishrsquos gill under the micro-
scope CAUTION Use care when working with micro-scopes and microscope slides
Draw and label a sketch of the gill filaments
Analysis1 Observe and Infer Why are the gills of fishes made up
of very thin tissue2 Predict How might a fish adjust to water that suddenly
has less oxygen 3 Explain Some fishes have a mutualistic relationship with
organisms such as small shrimp that ldquocleanrdquo gill filamentsby feeding on parasites that live on the gill tissue How isthis relationship beneficial to each organism
Gill Filaments
Gill Filaments
Water
Artery
Vein
Water
Capillary networks in filament
0793-0802 C30S1 BDOL-829900 8404 959 PM Page 795
Most fishes have paired finsFishes in the classes Chondrich-
thyes and Osteichthyes have pairedfins Fins are fan-shaped membranesthat are used for balance swimmingand steering Fins are attached to andsupported by the endoskeleton and are important in locomotion The paired fins of fishes illustrated inFigure 303 foreshadowed the devel-opment of limbs for movement onland and ultimately of wings for flying
Fishes have developed sensory systems
All fishes have highly developed sen-sory systems Cartilaginous and bonyfishes have an adaptation called the lat-eral line system that enables them tosense objects and changes in their envi-ronment The lateral line system is aline of fluid-filled canals running alongthe sides of a fish that enable it todetect movement and vibrations in thewater Find out more about the lateralline system by doing the Problem-Solving Lab on this page
Fishes have eyes that allow them tosee objects and contrasts betweenlight and dark in the water as wellThe amount of vision varies greatlyamong fishes Some fishes that live inareas of the ocean where there is nolight may have reduced almost non-functional eyes
Some fishes also have an extremelysensitive sense of smell and can detectsmall amounts of chemicals in thewater Sharks can follow a trail ofblood through the water for severalhundred meters This ability helpsthem locate their prey
Most fishes have scalesCartilaginous and bony fishes have
skin covered by intermittent or over-lapping rows of scales Scales are thinbony plates formed from the skin
Tom BrakefieldDRK Photo
Figure 303The paired fins of a fish include the pectoral fins and the pelvic fins Fins found on the dorsal and ventral surfaces can include the dorsal fins and anal fin
Dorsal fins
Pelvicfins
PectoralfinAnal
fin
Caudalfin
796 FISHES AND AMPHIBIANS
Think CriticallyWhy is having a lateral line system important Aside fromother senses including sight and smell most fishes also have alateral line system
Solve the ProblemThe lateral line system runs along either side of a fish in itsskin Vibrations in the water cause the gelatin-like fluid in thelateral line system to move which stimulates the receptor cellsto send messages to the fishrsquos brain The fish receives informa-tion about the location of objects in the water such as coralrocks other fishes and prey organisms
Thinking Critically1 Infer If a fishrsquos lateral line system were damaged and
unable to function what effect could that have on the fish2 Explain Why might a lateral line system be important for
fishes that live in the abyss where there is no light3 Hypothesize Fishes in a school have the ability to change
direction almost instantly Form a hypothesis that explainshow the lateral line system allows fishes to achieve this
Gelatin-like fluidReceptor cells
Nerve
Lateral line
0793-0802 C30S1 BDOL-829900 8404 1000 PM Page 796
Scales shown in Figure 304 can betoothlike diamond-shaped cone-shaped or round Shark scales aresimilar to teeth found in other verte-brates The age of some species offishes can be estimated by countingannual growth rings in their scales
Describe the differ-ent shapes scales can have
Jaws evolved in fishesAn important event in vertebrate
evolution was the development ofjaws in ancestral fishes The advan-tage of jaws is that they enable an ani-mal to grasp and crush its prey withgreat force Jaws also allowed earlyfishes to prey on a greater variety oforganisms This among other fac-tors explains why some early fisheswere able to grow to such great sizeFigure 305 shows the evolution ofjaws in fishes
When you think of a shark do youimagine gaping jaws and rows ofrazor-sharp teeth Sharks have up to20 rows of teeth that are continuallyreplaced Their teeth point backwardsto prevent prey from escaping oncecaught Sharks are among the moststreamlined of all fishes and are welladapted for life as predators
Most fishes have bony skeletonsThe majority of the worldrsquos fishes
belong to the class Osteichthyes thebony fishes Bony fishes a successfuland widely distributed class differgreatly in habitat size feeding behav-ior and shape All bony fishes haveskeletons made of bone rather thancartilage as found in other classes offishes Bone is the hard mineralizedliving tissue that makes up theendoskeleton of most vertebrates
301 FISHES 797(t)George BernardAnimals Animals (bl)Scott CamazinePhoto Researchers (br)Chuck BrownPhoto Researchers
Figure 304Fishes can be classified by the typeof scales present Diamond-shapedscales (A) are common to bonyfishes such as gars Bony fishessuch as chinook salmon haveeither cone-shaped or round scales(B) Tooth-shaped scales (C) arecharacteristic of the sharks
Gill arches
Gill arches
Gill slitsGill slits
Skull JawsJawless filter-feeding fish
Beginning of jaw formation Fish with jaws
Figure 305Jaws evolved from thecartilaginous gill archesof early jawless fishesTeeth evolved from skin
AA
BB
CC
LM Magnification 40
0793-0802 C30S1 BDOL-829900 8404 1000 PM Page 797
In general the development of bonewas important for the evolution offishes and vertebrates It allowed fishesto adapt to a variety of aquatic environ-ments as shown in Figure 306 andeventually to land
Bony fishes have separate vertebrae that provide flexibility
The evolution of a backbone com-posed of separate hard segments calledvertebrae was significant in providingthe major support structure of the ver-tebrate skeleton Separate vertebraeprovide great flexibility This is espe-cially important for fish locomotionwhich involves continuous flexing of
the backbone You can see how modernbony fishes propel themselves throughwater in Figure 307 Some fishes areeffective predators in part because ofthe fast speeds they can attain as aresult of having a flexible skeleton
Bony fishes evolved swim bladders
Another key to the evolutionary suc-cess of bony fishes was the evolution ofthe swim bladder A swim bladder isa thin-walled internal sac found justbelow the backbone in most bonyfishes It can be filled with mostlyoxygen or nitrogenous gases that dif-fuse out of a fishrsquos blood A fish with a
798 FISHES AND AMPHIBIANS(l)Kit KittleCORBIS (c)Doug PerrineDRK Photo (r)Steinhart AquariumPhoto Researchers
Figure 306Bony fishes vary in appearance behavior and way of life
Figure 307Most bony fishes swimin one of three ways
An eel moves its entire bodyin an S-shaped pattern
AA mackerel flexes theposterior end of its body toaccentuate the tail-finmovement
B A tuna keeps its body rigidmoving only its powerful tailFishes that use this methodmove faster than all others
C
Predatory bony fishes such as thispike have sleek bodies withpowerful muscles and tail fins forfast swimming in freshwater lakesand rivers
C
Seahorses move slowlythrough the underwaterforests of seaweed where theylive They are unusual in thatthe males brood their youngin stomach pouches
B
Eels have a long snakelike bodyand can wriggle through mudand crevices in search of food
A
l
0793-0802 C30S1 BDOL-829900 8404 1001 PM Page 798
swim bladder can control its depth byregulating the amount of gas in thebladder The gas works like the gas ina blimp that allows the blimp tochange its height above the ground
Some fishes remove gases from theswim bladder by expelling themthrough a special duct that attachesthe swim bladder to the esophagus Infishes that do not have this duct theirswim bladders empty when gases dif-fuse back into the blood
Explain the functionof a swim bladder
Diversity of FishesFishes range in size from the tiny
dwarf goby that is less than 1 cm longto the huge whale shark that canreach a length of about 15 mmdashthelength of two school buses
Agnathans are jawless fishesLampreys and hagfishes belong to
the superclass Agnatha The skeletonsof agnathans as well as of sharks andtheir relatives are made of a toughflexible material called cartilageThough they do not have jaws theyare voracious feeders A hagfishFigure 308 has a toothed mouth and feeds on dead or dying fishes
It can drill a hole into a fish and suckout the blood and insides Parasiticlampreys use their suckerlike mouthsto attack other fishes They use theirsharp teeth to scrape away the fleshand then suck out the preyrsquos blood
Sharks and rays are cartilaginous fishes
Sharks skates and rays belong tothe class Chondrichthyes shown inFigure 309 These fishes like agna-thans possess skeletons composedentirely of cartilage Because livingsharks skates and rays are similar tospecies that swam the seas more than100 000 years ago they are consideredliving fossils Sharks are perhaps themost well-known predators of theoceans
301 FISHES 799
Figure 308When touched a hag-fishrsquos skin gives off atremendous amount ofmucus which makes itso slimy it is nearlyimpossible to catch
The hammerheadshark is large andfound in warmocean water It hastwo eyes that areat opposite endsof its flattenedextended skull
A
Most rays are ocean bottom dwellers butthe Atlantic manta ray prefers to glide alongjust below the waterrsquos surface
B
Figure 309Cartilaginous fishes includesharks skates and rays
(t)Brian ParkerTom Stack amp Associates (bl)BiosPeter Arnold Inc (br)Doug PerrineDRK Photo
0793-0802 C30S1 BDOL-829900 8404 1001 PM Page 799
Like sharks most rays are predatorsand feed on or near the ocean floorRays have flat bodies and broad pec-toral fins on their sides By slowlyflapping their fins up and down rayscan glide as they search for mollusksand crustaceans along the ocean floorSome species of rays have sharp spineswith poison glands on their long tailsthat they can use for defense Otherspecies of rays have organs that gener-ate electricity which can stun or killboth prey and predators
Subclasses of bony fishesScientists recognize two subclasses
of bony fishesmdashthe lobe-finnedfishes including lungfishes and theray-finned fishes Figure 3010 showsexamples of these subclasses Thelobe-finned fishes are represented byseven living species six species oflungfishes which have both gills and
lungs and the coelacanth shown inFigure 3010B In the ray-finnedfishes such as catfish perch salmonand cod fins are fan-shaped mem-branes supported by stiff spines calledrays You can compare the interrela-tionships between the structures of aray-finned fish in Figure 3011
Origins of FishesScientists have identified fossils
of fishes that existed during the lateCambrian Period 500 million yearsago At this time ostracoderms (OHS trah koh durmz) early jawlessfishes were the dominant verte-brates on Earth Most ostracodermsbecame extinct at the end of theDevonian Period about 354 millionyears ago Present-day agnathansappear to be the direct descendantsof ostracoderms
800 FISHES AND AMPHIBIANS(tr)Tom McHughPhoto Researchers (l)Steinhart AquariumPhoto Researchers (br)Ron amp Valerie TaylorBruce Coleman Inc
Figure 3010Lobe-finned fishes and ray-finned fishes are the subclasses of the bony fishes
Lungfishes represent an ancient group oflobe-finned fishesLungfishes such as thisAfrican lungfish haveboth gills and lungs
A
The coelacanth anothertype of lobe-finned fishwas thought to be extinctuntil living coelacanthswere caught off the coastof Africa in 1938
B
You can easily see the raysthat support the pectoral finsof this flying fish an exampleof a ray-finned fish
C
PhysicalScience
Connection
Buoyancy anddensity of fluidsA fluidmdasha liquid ora gasmdashexerts anupward buoyantforce on an objectimmersed in itThis buoyant forceis equal to theweight of the fluiddisplaced by theobject The weightof fluid dependson the objectrsquosvolume When afishrsquos swim bladderis inflated thevolume of the fishincreases and thebuoyant force onthe fish increasesHow does thisaffect the depth ofthe fish in water
0793-0802 C30S1 BDOL-829900 8404 1002 PM Page 800
301 FISHES 801
Lateral line system When fishes swim past obstacles pressure changes occur in the water Fishescan detect these changes with their lateral linesystems which enable them to swim in the dark and in complex coral reefs
AA
Gills Gills are thin blood-vessel-richtissues where gases are exchanged
DD
Scales Scales arecovered with slipperymucus allowing a fish tomove through water withminimal friction
CC
Fins The structureand arrangement of fins are related to aparticular type oflocomotion Tropicalfishes that live amongcoral reefs tend to havesmall fins that allowmaneuvering betweenrocks and in crevices Atuna has larger broadfins for moving quicklythrough open water
EE
Kidney
Urinary bladder
Reproductive organ
StomachIntestine
LiverHeart
Rainbow troutOncorhynchus mykiss
A Bony FishFigure 3011The bony fishes class Osteichthyes include some of theworldrsquos most familiar fishes such as the bluegill trout min-now bass swordfish and tuna Though diverse in generalappearance and behavior bony fishes share some commonadaptations with other fish classes Critical Thinking Explainhow the different organ systems in bony fishes worktogether allowing a fish to function in the water
Swim bladder A swim bladder is a gas-filled sac thatenables a fish to control the depth at which it swims Tobecome more buoyant and rise in the water the fish inflatesits swim bladder with gases extracted from the water Thefish reabsorbs these gases to become less buoyant and sink
BB
Pat amp Tom LessonPhoto Researchers
0793-0802 C30S1 BDOL-829900 8404 1002 PM Page 801
Understanding Main Ideas1 Identify three characteristics of fishes
2 Compare how modern jawless fishes and cartilagi-nous fishes feed
3 Identify the function of the circulatory system infishes Explain how it works
4 Explain how a flexible skeleton is related to locomotion in fishes
Thinking Critically5 Why was the development of jaws an important
step in the evolution of fishes
6 Summarize Construct a diagram that shows the phylogeny of fishes and the development of important characteristics in their evolution For more help refer to Summarize in the SkillHandbook
SKILL REVIEWSKILL REVIEW
802 FISHES AND AMPHIBIANS
Figure 3012Ostracoderms the earli-est vertebrate fossilsknown were character-ized by bony externalplates covering the bodyand a jawless mouthInfer How did thesejawless ostracodermsobtain food
Weighed down by heavy bonyexternal armor ostracoderms shownin Figure 3012 were fearsome-looking animals that swam sluggishlyover the murky seafloor Although allostracoderms had cartilaginous skele-tons they also had shields of bonecovering their heads and necks Thedevelopment of bone in early verte-brates was an important evolutionarystep because bone provides a place formuscle attachment which improveslocomotion In ancestral fishes bonethat formed into plates provided pro-tection as well
Scientists hypothesize that the jaw-less ostracoderms were the common
ancestors of all fishes Modern carti-laginous and bony fishes evolvedduring the mid-Devonian PeriodLobe-finned fishes such as coela-canths (SEE luh kanths) are anotherancient group appearing in the fossilrecord about 395 million years agoThey are characterized by lobelikefleshy fins and live at great depthswhere they are difficult to find Thelimblike skeletal structure of fleshyfins is thought to be an ancestral con-dition of all tetrapods (animals withfour limbs) The earliest tetrapodsdiscovered also had gills and thereforewere still aquatic
Anaspid
Heterostracan
Cephalaspid
cabdolglencoecomself_check_quiz
0793-0802 C30S1 BDOL-829900 8404 1003 PM Page 802
302SECTION PREVIEWObjectivesRelate the demands of a terrestrial environ-ment to the adaptationsof amphibiansRelate the evolution of the three-chamberedheart to the amphibianlifestyle
Review Vocabularymetamorphosis a series of
changes in an organismcontrolled by chemicalsubstances (p 751)
New Vocabularyectothermvocal cord
302 AMPHIBIANS 803
What is an amphibianThe striking transition from a completely aquatic larva to an air-
breathing semiterrestrial adult gives the class Amphibia (am FIHB ee uh) itsname which means ldquodouble liferdquo The class Amphibia includes three ordersCaudata (kaw DAH tuh)mdashsalamanders and newts Anura (uh NUHR uh)mdashfrogs and toads and Apoda (uh POH duh)mdashlegless caecilians shown in
Figure 3013 Amphibians havethin moist skin and most havefour legs Although most adultamphibians are capable of a terres-trial existence nearly all of themrely on water for reproductionFertilization in most amphibians isexternal and water is needed as amedium for transporting spermAmphibian eggs lack protectivemembranes and shells and must belaid in water or other moist areasReview some adaptations thatallow frogs to live a ldquodouble liferdquoin Figure 3014 on the next page
Amphibians
(tl)OSFAnimals Animals (tr)Joe McDonaldDRK Photo (b)Zig LeszczynskiAnimals Animals
Figure 3013Caecilians orderApoda are long limb-less amphibians
A Double LifeUsing Prior KnowledgeWhen you think of an amphibian do you picture a jumping frog Maybe a salamander sitting on a log Perhaps you think of tadpoles in pond water Amphibians are a diverse group of animals that can be found both on land and in water In this section you willexamine the characteristics ofamphibians that allow them to spend at least part of their lives on landInfer Make a list of charac-teristics that are necessary foran animal to live successfully on land
Pickerel frog (above)and tadpoles (inset)
0803-0815 C30S2 BDOL-829900 8404 936 PM Page 803
BDOL-302
null
4863796
A FrogFigure 3014Many species of frogs look similar As adults they have short bulbous bodies with no tails This adaptation allowsthem to jump more easily Critical Thinking Compare and contrast the lateral line system of a fish to thetympanic membrane of a frog
Rod PlanckPhoto Researchers
Green frog Rana clamitans
Eyes Some frogsrsquo eyesprotrude from the tops oftheir headsmdashan adaptationthat enables them to staysubmerged in the waterwith only their eyes abovethe surface
AA
Tongue A frogrsquos tongueis long sticky and fastenedto the front of the mouthThese adaptations allowfrogs to snare their preysuch as flies with amazingaccuracy
CC
Calls Male frogs usesound to attract femalesFemales have distinctcalls to indicate whetheror not they are willingto mate
EE
804 FISHES AND AMPHIBIANS
Vocalcords
Heart
Liver
Intestine
Fat bodies
Backbone
Tympanic membrane Vibrationsfrom water or air are picked up by thetympanic membrane and transmitted tothe inner ear and then to the brain Thetympanic membrane also amplifies thesounds frogs make
BB
Lungs Lungs enable adultamphibians to breathe air
DD
Legs The hind legs of afrog are muscular If you have ever tried to catch afrog you can appreciate these powerful leg muscles
FF
0803-0815 C30S2 BDOL-829900 8404 937 PM Page 804
Adult frog
Young frogs have structuresneeded for life on land
Tadpoles with legs feedon plants in the water
Young legless tadpoles live off yolk storedin their bodies
BB
Fertilized eggsAA
CC
DDEE
Amphibians are ectothermsAmphibians are more common in
regions that have warm temperaturesall year because they are ectothermsAn ectotherm (EK tuh thurm) is ananimal that has a variable body temperature and gets its heat fromexternal sources Because many bio-logical processes require particulartemperature ranges in order to occuramphibians become dormant inregions that are too hot or cold forpart of the year During such timesmany amphibians burrow into themud and stay there until suitable con-ditions return
Amphibians undergo metamorphosis
Unlike fishes most amphibians gothrough the process of metamorpho-sis Fertilized eggs hatch into tadpolesthe aquatic stage of most amphibiansYou can compare tadpoles with adult
frogs in the MiniLab on the next pageTadpoles possess fins gills and a two-chambered heart as seen in fishes Astadpoles grow into adult frogs andtoads they develop legs lungs and athree-chambered heart Figure 3015shows this life cycle
Young salamanders resemble adultsbut as aquatic larvae they have gillsand usually have a tail fin Most adultsalamanders lack gills and fins Theybreathe through their moist skin orwith lungs Salamanders in the familyPlethodontidae have no lungs andbreathe only through their skinCompletely terrestrial salamanderspecies do not have a larval stage theyoung hatch as smaller versions ofadults Most salamanders have fourlegs for moving about but a few haveonly two front legs
Explain the processof metamorphosis in amphibians
302 AMPHIBIANS 805
Adult frog
Young frogs have structuresneeded for life on land
Tadpoles with legs feedon plants in the water
Young legless tadpoles live off yolk storedin their bodies
BB
Fertilized eggsAA
CC
DDEE
Figure 3015The amphibian life cycle caninclude an aquatic tadpole stageand a terrestrial adult stage
parthenogenesisfrom the Greekword parthenosmeaning ldquovirginrdquoand the Latin wordgenesis meaningldquobirthrdquo Someamphibians reptilesand insects repro-duce asexuallythrough partheno-genesis Insects usu-ally produce allmales while reptilesand amphibians usu-ally produce allfemales
0803-0815 C30S2 BDOL-829900 8404 938 PM Page 805
Walking requires more energyThe laborious walking of early
amphibians required a great deal ofenergy from food and large amountsof oxygen for aerobic respiration Theevolution of the three-chamberedheart in amphibians ensured that cellsreceived the proper amount of oxy-gen This heart was an important evo-lutionary transition from the simplecirculatory system of fishes
In the three-chambered heart ofamphibians one chamber receivesoxygen-rich blood from the lungsand skin and another chamberreceives oxygen-poor blood from thebody tissues Blood from both cham-bers then moves to the third cham-ber which pumps oxygen-rich bloodto body tissues and oxygen-poorblood back to the lungs and skin so it can pick up more oxygen Thisresults in some mixing of oxygen-rich and oxygen-poor blood in theamphibian heart and in blood vesselsleading away from the heart Thusin amphibians the skin is much moreimportant than the lungs as an organfor gas exchange
Because the skin of an amphibianmust stay moist to exchange gasesmost amphibians are limited to life onthe waterrsquos edge or other moist areasSome newts and salamanders remaintotally aquatic Amphibians such astoads have thicker skin and althoughthey live primarily on land they stillmust return to water to reproduce
Amphibian DiversityBecause most amphibians still
complete part of their life cycle inwater they are limited to the edges ofponds lakes streams and rivers or toareas that remain damp during part ofthe year Although they may not beeasily seen amphibian species arenumerous worldwide
George BernardAnimals Animals
Compare and ContrastFrog and Tadpole Adaptations An adult frog and its larval stagemdasha tadpolemdashareadapted to different habitats How are the structures of a frog and a tadpole adapted to their environments
ProcedureCAUTION Wear disposable gloves and use a forceps whenhandling preserved specimens Always wash your hands after working with live or preserved animals Copy the data table Examine a living or preserved adult frog and larval
(tadpole) stage Observe the first seven traits listed Complete your data
table for these observations$ Use references to fill in the information for the last three
traits listed
Analysis1 Explain How do hind leg muscles aid adult frog survival2 Analyze Correlate the type of respiratory organ in an
adult and a tadpole with their differing habitats 3 Analyze Correlate the type of appendages (arm leg tail)
in an adult and a tadpole with their differing habitats4 Analyze Correlate mouth size in an adult and a tadpole
with their differing diet5 Explain How do eyes aid in the survival of both stages6 Think Critically How can skin color and texture aid in
adult frog survival
Rana temporaria
Data Table
Trait or Information Tadpole Adult
Limbs present
Eyes present
Tympanic membrane present
Tail present
Mouth present
Nature of skin (color and texture)
General size
Respiratory organ type
Diet
Habitat
0803-0815 C30S2 BDOL-829900 8404 939 PM Page 806
Frogs and toads belong to the order Anura
Frogs and toads are amphibians withno tails Frogs have long hind legs andsmooth moist skin Toads have shortlegs and bumpy dry skin Like fishesfrogs and toads have jaws and teethAdult frogs and toads are predators thateat invertebrates such as insects andworms Many species of frogs andtoads secrete chemicals through theirskin as a defense against predators Youcan find out more about poisonousfrogs in the Connection to Chemistry atthe end of this chapter
Frogs and toads also have vocalcords that are capable of producing awide range of sounds Vocal cordsare sound-producing bands of tissuein the throat As air moves over thevocal cords they vibrate and causemolecules in the air to vibrate Inmany male frogs air passes over thevocal cords then passes into a pair ofvocal sacs lying underneath thethroat as shown in Figure 3016
Most frogs and toads spend part oftheir life cycle in water and part onland They breathe through lungs orthrough their thin skins As a resultfrogs and toads often are among thefirst organisms to be exposed to pol-lutants in the air on land or in thewater Declining numbers of frogspecies or deformities in local frogssometimes indicate the presence ofpollutants in the environment
Analyze the impor-tance of environmental conditionsto a frogrsquos health
Salamanders belong to the order Caudata
Unlike a frog or toad a salamanderhas a long slender body with a neckand tail Salamanders resemblelizards but have smooth moist skinand lack claws Some salamanders are
totally aquatic and others live indamp places on land They range insize from a few centimeters in lengthup to 15 m The young hatch fromeggs look like small salamanderadults and are carnivorous
Caecilians are limbless amphibians
Caecilians are burrowing amphib-ians have no limbs and have a short orno tail Caecilians are primarily tropi-cal animals with small eyes that oftenare blind They eat earthworms andother invertebrates found in the soilAll caecilians have internal fertilization
Origins of AmphibiansImagine a time 360 million years
ago when the inland freshwater seaswere filled with carnivorous fishesOne type of tetrapod had evolved thatretained gills for breathing and afinned tail for swimming Earlytetrapods may have used their limbsto move on the bottom of marshlandsfilled with plants In later fossils thefour limbs are found further belowthe body to lift it off the ground
302 AMPHIBIANS 807William LeonardDRK Photo
Figure 3016Most male frogs havethroat pouches thatalong with the tym-panic membraneincrease the loudness oftheir calls Infer Howmight this adaptationbenefit frogs
0803-0815 C30S2 BDOL-829900 8404 940 PM Page 807
Most likely amphibians arose as theirability to breathe air through well-developed lungs evolved The successof inhabiting the land depended onadaptations that would provide supportprotect membranes involved in respira-tion and provide efficient circulation
Challenges of life on landLife on land held many advantages
for early amphibians There was alarge food supply shelter and nopredators In addition there wasmuch more oxygen in air than in
water However land life also heldmany dangers Unlike the tempera-ture of water which remains fairlyconstant air temperatures can varygreatly In addition without the sup-port of water the body was clumsyand heavy Some of the efforts byearly amphibians to move on landprobably were like movements ofpresent-day salamanders The legs ofsalamanders are set at right angles tothe body You can see in Figure 3017why the bellies of these animals mayhave dragged on the ground
Amphibians first appeared about360 million years ago Amphibiansprobably evolved from an aquatictetrapod as shown in Figure 3018around the middle of the PaleozoicEra At that time the climate onEarth is known to have become warmand wet ideally suited for an adaptiveradiation of amphibians Able tobreathe through their lungs gills orskin amphibians became for a timethe dominant vertebrates on land
(t)MC ChamberlainDRK Photo (c)MP KahlDRK Photo (b)William LeonardDRK Photo
Figure 3017Adaptation to life on landinvolves the positioning oflimbs The evolution of ani-mal with four limbs led tothe diversification of landvertebrates
Reptiles such as this crocodile have legs onthe sides of their bodies like amphibians butthe limbs have joints that enable them to bendand hold the body up off the ground
C
Mammal bodies are raised above the groundwith limbs that are positioned underneath the body This position allows greater speed of locomotion making mammals such as this cheetah the fastest-moving land animals
B
The salamander anamphibian has legsthat extend at rightangles to its body
A
808 FISHES AND AMPHIBIANS
Figure 3018Transitional fossils of aquatictetrapods from the DevonianPeriod show that they had amphib-ian characteristics but they alsoretained some fishlike features
0803-0815 C30S2 BDOL-829900 8404 940 PM Page 808
Understanding Main Ideas1 Describe the events that may have led early ani-
mals to move to land
2 Identify and describe three characteristics ofamphibians
3 List several reasons why amphibians are depen-dent on water
4 Relate the demands of a terrestrial environmentto the adaptations of amphibians
Thinking Critically5 How does a three-chambered heart enable
amphibians to obtain the energy needed formovement on land
6 Get the Big Picture Make a diagram that tracesthe evolutionary development of amphibians fromlungfishes For more help refer to Get the BigPicture in the Skill Handbook
SKILL REVIEWSKILL REVIEW
302 AMPHIBIANS 809
Frogs and Toads3700 species
Salamanders369 species
Caecilians168 species
Placoderms
Lobe-finnedfishes
7 species Ray-finned Fishes18 000 species
Sharksand Rays850 species
Ostracoderms
Earlytetrapod
Reptiles
Lampreys17 species
43 speciesHagfishes
Osteichthyes
Agnatha
Amphibians
Chondrichthyes
Species numbers are approximate and subject to change pending discoveries or extinctions
Figure 3019The radiation of classes of fishesand orders of amphibians showstheir relationships
ANIMALS
Recall that early vertebrates evolvedfrom swimming fishes to aquatictetrapods Scientists have found fossilevidence that supports the hypothesisthat limbs first evolved in aquatic ani-mals Some of these aquatic verte-brates had lungs and evolved intoanimals that crawled on the bottom of
marshlands and finally evolved tofully developed amphibians that couldlive on land Although the fossilrecord for fishes and amphibians is incomplete most scientists agree that the relationships shown in Figure 3019 represent the best fit forthe available evidence
cabdolglencoecomself_check_quiz
0803-0815 C30S2 BDOL-829900 8404 940 PM Page 809
810 FISHES AND AMPHIBIANS
Before You BeginTo help identify organismstaxonomists have devel-oped classification keys Adichotomous key can con-sist of a set of questionsfor identifying organismsWhen you use this type ofa dichotomous key youanswer yes or no to aquestion based on thecharacteristics of theorganism you are trying to identify Depending onyour answer you aredirected to another ques-tion that further narrowsdown the identificationWhen you have answeredall the questions you willarrive at the name of theorganism or the group towhich it belongs In thislab you will create a sim-ple dichotomous key tohelp you identify differentamphibians
Making a DichotomousKey for Amphibians
ProblemHow is a dichotomous key made
ObjectivesIn this BioLab you will Design and construct a dichotomous key for amphibians Classify organisms on the basis of structural characteristics
Materialssample keys from guidebooksfield guides for amphibian identification
Skill HandbookIf you need help with this lab refer to the Skill Handbook
1 Study the field guides for amphibians Note characteris-tics such as the number of legs present length of hindlegs length of tail (if present) texture of skin and thestructure of gills (if present)
2 Make a list of yes or no questions based on the differentcharacteristics of amphibians
3 Begin with a broad question then based on their answerdirect the user to another question that will further nar-row down the identification of an organism
4 Continue to construct your key using the question-and-answer system until the user can classify an organism intoa particular group such as family or genus
5 Exchange dichotomous keys with another team Usetheir key to classify some amphibians
PROCEDUREPROCEDURE
PREPARATIONPREPARATION
0803-0815 C30S2 BDOL-829900 8404 943 PM Page 810
302 AMPHIBIANS 811
ANALYZE AND CONCLUDEANALYZE AND CONCLUDE
1 Compare and Contrast Was the dichoto-mous key you constructed exactly like thoseof other students Explain
2 Evaluate What characteristics were mostuseful for making a classification key foramphibians What characteristics were notuseful for making your key
3 Think Critically Why do keys typically offertwo answer choices rather than a larger num-ber of choices
4 Give reasons why anotherstudent might not be able to identify the groupto which an amphibian belongs using your key
ERROR ANALYSIS
Field Investigation Find out which amphi-bians live near you and make a dichotomouskey specific for the amphibians in your areaTest the accuracy of your key by using it inthe field to classify amphibians
Web Links To find out more about amphibians visitcabdolglencoecomamphibians
00 Second Proof
0803-0815 C30S2 BDOL-829900 8404 946 PM Page 811
Painkiller Frogs
The most colorful frogs in the world are found in South and Central America These
poisonous frogs including 130 species of theDendrobatidae family range in size from 1 to5 cm Although all frogs have glands that producesecretions these frogs secrete toxic chemicalsthrough their skin A predator will usually dropthe foul-tasting frog when it feels the numbing orburning effects of the poison in its mouth
The frogs advertise their poisonous personali-ties by bright coloration they may be red orblue solid colored marked with stripes or spotsor have a mottled appearance The poisonsecreted by these frogs is used by some nativepeople to coat the tips of the darts that they usein their blow guns for hunting Thus these frogsare known as poison-arrow frogs
The secretions of the poison-arrow frogs ofthe frog family Dendrobatidae are alkaloid tox-ins The chemical structure of an alkaloid toxinincludes a ring consisting of five carbon atomsand one nitrogen atom The toxins secreted bypoisonous frogs act on an ion channel betweennerve and muscle cells Normally the channel isopen to allow movement of sodium potassiumand calcium ions The toxins can block the flowof potassium and stop or prolong nerve impulsetransmission and muscle contraction One groupof alkaloids affects the transport of calcium ionswhich are responsible for muscle contractionCurrent research indicates that these alkaloidsmay have clinical applications for muscle dis-eases and as painkillers
Frog poison eases pain Recent researchshows that a drug derived from the extract fromsome poison-arrow frogs including Epipedobatestricolor works as a powerful painkiller The drugABT-594 may have the same benefits as mor-phine but not the side effects Morphine is the primary drug used to treat the severe and
unrelenting pain caused by cancer and seriousinjuries Side effects of morphine include sup-pressed breathing and addiction The ldquofrogdrugrdquo does not interfere with breathing and doesnot appear to be addictive in initial testingAnother benefit of ABT-594 is that as it blockspain it does not block other sensations such astouch or mild heat One day pain that you expe-rience might be eased by a frog
812 FISHES AND AMPHIBIANSJohn NethertonAnimals Animals
Poison-arrow frog Epipedobates tricolor
Alkaloid toxinCl
O
N
N
H
Evaluate the Impact of Research Research onnewly discovered organisms such as poisonousfrogs may result in drugs to treat specific disor-ders in humans Evaluate the impact of thisresearch on scientific thought and society Identifydiseases that could be treated using toxins frompoisonous frogs
To find out more about poisonous frogsvisit cabdolglencoecomchemistry
0803-0815 C30S2 BDOL-829900 8404 948 PM Page 812
Section 301Key Concepts Fishes are vertebrates with backbones and
nerve cords that have expanded into brains Fishes belong to four classes two classes of
jawless fishes lampreys and hagfishes thecartilaginous sharks and rays and the bonyfishes Bony fishes are made up of twogroups the lobe-finned fishes includinglungfishes and the ray-finned fishes
Jawless cartilaginous and bony fishes mayhave evolved from ancient ostracoderms
Vocabularycartilage (p 799)fin (p 796)lateral line system
(p 796)scale (p 796)spawning (p 795)swim bladder (p 798)
Fishes
Key Concepts The class Amphibia includes three orders
Caudatamdashsalamanders and newts Anuramdashfrogs and toads and Apodamdashlegless caecilians
Adult amphibians have three-chamberedhearts that provide oxygen to body tissuesbut most gas exchange takes place throughthe skin
Land animals face problems of dehydra-tion gas exchange in the air and supportfor heavy bodies Amphibians possessadaptations suited for life on land
Amphibians probably evolved from ancient aquatic tetrapods
Vocabularyectotherm (p 805)vocal cord (p 807)Amphibians
STUDY GUIDESTUDY GUIDE
CHAPTER 30 ASSESSMENT 813(t)Tom BrakefieldDRK Photo (b)OSFAnimals Animals
Section 302
To help review informa-tion on fishes use the OrganizationalStudy Fold on page 793
Fishes
Class Organisms Characteristics
Myxini Hagfishes Jawless cartilaginous skeleton gills
Cephalaspidomorphi Lampreys Jawless cartilaginous skeleton gills
Chondrichthyes Sharks skates rays Jaws cartilaginous skeleton paired fins gills scales internal fertilization
Osteichthyes Lobe-finned fishes Jaws bony skeleton paired fins ray-finned fishes gills scales swim bladder
cabdolglencoecomvocabulary_puzzlemaker
0803-0815 C30S2 BDOL-829900 8404 949 PM Page 813
Review the Chapter 30 vocabulary words listed inthe Study Guide on page 813 Match the wordswith the definitions below
1 thin bony plates formed from the skin of fish 2 thin-walled internal sac found just below
the backbone in bony fishes3 fan-shaped membranes that are used for bal-
ance swimming and steering by fish4 a line of fluid-filled canals running along the
sides of a fish
5 Which of the following characteristics do allvertebrates have at some point in theirdevelopment A bilateral symmetry exoskeletons lungsB lungs postanal tail backboneC pharyngeal pouches notochord backboneD closed circulatory systems segmented
bodies external fertilization6 In general the respiratory system and circu-
latory system of fishes as illustrated beloware composed of ________A gills and a two-chambered heartB gills and a three-chambered heartC gills and a four-chambered heartD none of the above
7 How is the word amphibia related to theorganisms classified in this groupA Most amphibians spend part of their lives
in water and part on landB Amphibians live their entire lives on landC Amphibians use swim bladders for
breathing in water but use lungs on landD Many amphibians have a two-chambered
heart that develops into a three-chamberedheart when the animal matures
8 Advantages to life on land for early amphib-ians included ________A more food and no predatorsB greater temperature variationsC more food and more predatorsD less oxygen in the air than water
9 Complete the following concept map byusing the following vocabulary terms lat-eral line system scales swim bladder
10 Open Ended Relate the importance of theevolution of bone in fishes to the evolutionof vertebrates
11 Open Ended Relate the different types ofbody shapes of fishes to the habitat andbehavior of fishes
12 Open Ended Hypothesize how a fish with-out a swim bladder is able to maintain orvary its position in the water column
13 Writing in Biology Compare and contrastthe advantages and disadvantages of the dif-ferent reproductive methods of fishes
14 There are sev-eral interpretations of how fishes can beclassified Visit toinvestigate the different ways fish groups arecurrently classified Present the results ofyour research to your class in the form of aposter or multimedia presentation
REAL WORLD BIOCHALLENGE
Fishes
are vertebrates that
two-chamberedheart
1 2
3
have a
sense vibrations
with a
have a
protect skin with
814 CHAPTER 30 ASSESSMENT
cabdolglencoecom
cabdolglencoecomchapter_test
0803-0815 C30S2 BDOL-829900 8404 950 PM Page 814
CHAPTER 30 ASSESSMENT 815
15 Design an Experiment Monkey frogs livein extremely dry regions of South AmericaThey secrete wax from skin glands andspread the wax over their bodies Form ahypothesis about the function of this waxand design a controlled experiment thatwould test your hypothesis
16 Writing in Biology Scientists do not knowthe ultimate effect of stocking freshwaterecosystems with fishes for food and sportDecline of native species has been observedin areas where stocking occurs Give possi-ble reasons that explain why native speciesdecline when new species are introduced
Constructed ResponseGrid InRecord your answers on your answer document
21 Open Ended You are trying to find the optimum pH for hatching frog eggs Design a controlledexperiment that would yield quantitative data
22 Open Ended What might frogs be communicating when they make vocalizations Explain whyscientists use frog calls to identify different species of frogs
cabdolglencoecomstandardized_test
Multiple ChoiceUse this diagram to answer question 17
17 The sequence that best describes amphibiandecline is ________A fungus infection increases frogsrsquo risk for
damage by UV light caused by intensedryness
B intense dryness reduces pond depthcausing more exposure to UV light thatincreases risk for fungus infection
C intense dryness causes an increase in UVlight that kills frogs
D increase in the depth of ponds causesmore fungus infections in frogs
Use the following graph to answer questions 18ndash20
18 How many eggs hatched at 20degCA 150 C 95B 120 D 65
19 At which temperature did the fewest eggshatchA 15degC C 25degCB 20degC D 30degC
20 Based on the information presented in thegraph which temperature would you use foroptimal hatching of eggsA 15degC C 25degCB 20degC D 30degC
Nu
mb
er o
f fr
og
eg
gs
hat
chin
g
Temperature15˚C 20˚C 25˚C 30˚C
60
30
90
120
150
180
Number of Frog Eggs Hatching at VariousTemperatures in 5 Days
Global climate change
Intense dry events
Reduced water depth in ponds
Frog embryos exposed to more ultraviolet (UV) light
Increased risk of infection
Increased rates of infection by fungus
0803-0815 C30S2 BDOL-829900 8404 951 PM Page 815
- Biology The Dynamics of LifemdashCalifornia Edition
-
- Contents in Brief
-
- The California Biology Handbook
-
- California BiologyLife Sciences Content Standards
-
- California Content Standards to Biology The Dynamics of Life
- Biology The Dynamics of Life to California Content Standards
-
- How to Master the Content Standards
- Standards Practice Countdown
-
- Table of Contents
-
- Unit 1 What is biology
-
- Chapter 1 Biology The Study of Life
-
- Section 11 What is biology
-
- MiniLab 11 Predicting Whether Mildew Is Alive
- Careers in Biology Nature Preserve Interpreter
-
- Section 12 The Methods of Biology
-
- MiniLab 12 Testing for Alcohol
- Problem-Solving Lab 11
- Inside Story Scientific Methods
-
- Section 13 The Nature of Biology
-
- Problem-Solving Lab 12
- MiniLab 13 Hatching Dinosaurs
- Internet BioLab Collecting Biological Data
- Biology and Society Organic Food Is it healthier
-
- Chapter 1 Assessment
-
- BioDigest What is biology
- Unit 1 Standardized Test Practice
-
- Unit 2 Ecology
-
- Chapter 2 Principles of Ecology
-
- Section 21 Organisms and Their Environment
-
- MiniLab 21 Salt Tolerance of Seeds
- Problem-Solving Lab 21
- Careers in Biology Science Reporter
-
- Section 22 Nutrition and Energy Flow
-
- Problem-Solving Lab 22
- Physical Science Connection Conservation of Energy
- Physical Science Connection Conservation of Mass
- MiniLab 22 Detecting Carbon Dioxide
- Inside Story The Carbon Cycle
- Design Your Own BioLab How can one population affect another
- Biology and Society The EvergladesmdashRestoring an Ecosystem
-
- Chapter 2 Assessment
-
- Chapter 3 Communities and Biomes
-
- Section 31 Communities
-
- MiniLab 31 Looking at Lichens
- Problem-Solving Lab 31
-
- Section 32 Biomes
-
- Physical Science Connection Salinity and Density of a Solution
- Problem-Solving Lab 32
- MiniLab 32 Marine Plankton
- Inside Story A Tropical Rain Forest
- Investigate BioLab Succession in a Jar
- Connection to Literature Our National Parks by John Muir
-
- Chapter 3 Assessment
-
- Chapter 4 Population Biology
-
- Section 41 Population Dynamics
-
- MiniLab 41 Fruit Fly Population Growth
- Inside Story Population Growth
- Problem-Solving Lab 41
-
- Section 42 Human Population
-
- Problem-Solving Lab 42
- MiniLab 42 Doubling Time
- Investigate BioLab How can you determine the size of an animal population
- Connection to Chemistry Polymers for People
-
- Chapter 4 Assessment
-
- Chapter 5 Biological Diversity and Conservation
-
- Section 51 Vanishing Species
-
- MiniLab 51 Field Investigation
- Problem-Solving Lab 51
- Physical Science Connection Environmental Impact of Generating Electricity
- Physical Science Connection Wave Energy
-
- Section 52 Conservation of Biodiversity
-
- MiniLab 52 Conservation of Soil
- Problem-Solving Lab 52
- Internet BioLab Researching Information on Exotic Pets
- Connection to Art Photographing Life
-
- Chapter 5 Assessment
-
- BioDigest Ecology
- Unit 2 Standardized Test Practice
-
- Unit 3 The Life of a Cell
-
- Chapter 6 The Chemistry of Life
-
- Section 61 Atoms and Their Interactions
-
- Problem-Solving Lab 61
- Physical Science Connection Chemical Bonding and the Periodic Table
- Physical Science Connection Conservation of Mass in Chemical Reactions
- Careers in Biology WeedPest Control Technician
- MiniLab 61 Determine pH
-
- Section 62 Water and Diffusion
-
- Physical Science Connection The Structure of Water Molecules
- Physical Science Connection Density of Liquids
- Problem-Solving Lab 62
- MiniLab 62 Investigate the Rate of Diffusion
-
- Section 63 Life Substances
-
- Inside Story Action of Enzymes
- Design Your Own BioLab Does temperature affect an enzyme reaction
- BioTechnology The Good News and the Bad News About Cholesterol
-
- Chapter 6 Assessment
-
- Chapter 7 A View of the Cell
-
- Section 71 The Discovery of Cells
-
- Physical Science Connection Lenses and the Refraction of Light
- MiniLab 71 Measuring Objects Under a Microscope
-
- Section 72 The Plasma Membrane
-
- Problem-Solving Lab 71
- Physical Science Connection Solubility and the Nature of Solute and Solvent
-
- Section 73 Eukaryotic Cell Structure
-
- Problem-Solving Lab 72
- MiniLab 72 Cell Organelles
- Physical Science Connection Conservation of Energy
- Inside Story Comparing Animal and Plant Cells
- Investigate BioLab Observing and Comparing Different Cell Types
- Connection to Literature The Lives of a Cell by Lewis Thomas
-
- Chapter 7 Assessment
-
- Chapter 8 Cellular Transport and the Cell Cycle
-
- Section 81 Cellular Transport
-
- MiniLab 81 Cell Membrane Simulation
-
- Section 82 Cell Growth and Reproduction
-
- Problem-Solving Lab 81
- Problem-Solving Lab 82
- Inside Story Chromosome Structure
- MiniLab 82 Seeing Asters
-
- Section 83 Control of the Cell Cycle
-
- Problem-Solving Lab 83
- Investigate BioLab Where is mitosis most common
- Connection to Health Skin Cancer
-
- Chapter 8 Assessment
-
- Chapter 9 Energy in a Cell
-
- Section 91 The Need for Energy
-
- Problem-Solving Lab 91
-
- Section 92 Photosynthesis Trapping the Suns Energy
-
- MiniLab 91 Separating Pigments
- MiniLab 92 Use Isotopes to Understand Photosynthesis
- Inside Story The Calvin Cycle
- Biotechnology Careers Biochemist
-
- Section 93 Getting Energy to Make ATP
-
- Inside Story The Citric Acid Cycle
- Problem-Solving Lab 92
- MiniLab 93 Determine if Apple Juice Ferments
- Internet BioLab What factors influence photosynthesis
- Connection to Chemistry Plant Pigments
-
- Chapter 9 Assessment
-
- BioDigest The Life of a Cell
- Unit 3 Standardized Test Practice
-
- Unit 4 Genetics
-
- Chapter 10 Mendel and Meiosis
-
- Section 101 Mendels Laws of Heredity
-
- MiniLab 101 Looking at Pollen
- Problem-Solving Lab 101
-
- Section 102 Meiosis
-
- Problem-Solving Lab 102
- MiniLab 102 Modeling Crossing Over
- Inside Story Chromosome Mapping
- Internet BioLab How can phenotypes and genotypes of plants be determined
- Connection to Math A Solution from Ratios
-
- Chapter 10 Assessment
-
- Chapter 11 DNA and Genes
-
- Section 111 DNA The Molecule of Heredity
-
- Problem-Solving Lab 111
- Inside Story Copying DNA
-
- Section 112 From DNA to Protein
-
- Problem-Solving Lab 112
- MiniLab 111 Transcribe and Translate
-
- Section 113 Genetic Changes
-
- Physical Science Connection Gamma Radiation as a Wave
- Careers in Biology Genetic Counselor
- Problem-Solving Lab 113
- MiniLab 112 Gene Mutations and Proteins
- Investigate BioLab RNA Transcription
- BioTechnology Scanning Probe Microscopes
-
- Chapter 11 Assessment
-
- Chapter 12 Patterns of Heredity and Human Genetics
-
- Section 121 Mendelian Inheritance of Human Traits
-
- MiniLab 121 Illustrating a Pedigree
- Problem-Solving Lab 121
-
- Section 122 When Heredity Follows Different Rules
-
- Problem-Solving Lab 122
-
- Section 123 Complex Inheritance of Human Traits
-
- Inside Story The ABO Blood Group
- Problem-Solving Lab 123
- MiniLab 122 Detecting Colors and Patterns in Eyes
- Design Your Own BioLab What is the pattern of cytoplasmic inheritance
- Connection to Social Studies Queen Victoria and Royal Hemophilia
-
- Chapter 12 Assessment
-
- Chapter 13 Genetic Technology
-
- Section 131 Applied Genetics
-
- Problem-Solving Lab 131
-
- Section 132 Recombinant DNA Technology
-
- MiniLab 131 Matching Restriction Enzymes to Cleavage Sites
- Inside Story Gel Electrophoresis
- Problem-Solving Lab 132
-
- Section 133 The Human Genome
-
- MiniLab 132 Storing the Human Genome
- Biotechnology Careers Forensic Analyst
- Problem-Solving Lab 133
- Investigate BioLab Modeling Recombinant DNA
- BioTechnology New Vaccines
-
- Chapter 13 Assessment
-
- BioDigest Genetics
- Unit 4 Standardized Test Practice