Solutions for Seeleys Essentials Of Anatomy And Physiology 9th Us Edition by Vanputte

CHAPTER2 THECHEMICALBASISOFLIFE

CHAPTEROVERVIEW

Thischapterintroducesverybasicconceptsofchemistry,emphasizingthestructureofatomsandhow theycombine(formbonds).Thetypesofbonds,whichincludeionic,covalent,andhydrogenbonds,are introduced,andtheirimportanceinvariousmoleculesinthehumanbodyisdiscussed.Ionsaredefined, andalistofionsthatwillbediscussedinlaterchaptersispresented.Typesofchemicalreactionsare considered,andthefactorsthatinfluencereactionrates,includingenzymes,arediscussed.Studentsare introducedtotheconceptofpH,andthecharacteristicsthatmakewatersoimportantforlivingthings. Thechapteralsodiscussesthestructure,buildingblocks,importantexamples,andfunctionsoflarge organicmolecules,includingcarbohydrates,proteins,lipids,andnucleicacids.Adenosinetriphosphate anditsimportanceastheenergystorageformofthebodyisalsodiscussed.

STUDENTLEARNINGOUTCOMES

Afterreadingthissection,thestudentshouldbeableto:

2.01A.Definechemistryandstateitsrelevancetoanatomyandphysiology.

2.01B.Definematter,mass,andweight.

2.01C.Distinguishbetweenanelementandanatom.

2.01D.Defineatomicnumberandmassnumber.

2.01E.Namethesubatomicparticlesofanatom,andindicatetheirlocation.

2.01F.Compareandcontrastionicandcovalentbonds.

2.01G.Explainwhatcreatesahydrogenbondandrelateitsimportance.

2.01H.Differentiatebetweenamoleculeandacompound.

2.01I.Describetheprocessofdissociation.

2.02A.Summarizethecharacteristicsofsynthesis,decomposition,andexchangereactions.

2.02B.Explainhowreversiblereactionsproducechemicalequilibrium.

2.02C.Distinguishbetweenchemicalreactionsthatreleaseenergyandthosethattakeinenergy.

2.02D.Describethefactorsthatcanaffecttherateofchemicalreactions.

2.03A.DescribethepHscaleanditsrelationshiptoacidicandbasicsolutions.

2.03B.Explaintheimportanceofbuffersinorganisms.

2.04A.Distinguishbetweeninorganicandorganicmolecules.

2.04B.Describehowthepropertiesofoxygen,carbondioxide,andwatercontributetotheirphysiological functions.

2.05A.Describethestructuralorganizationandmajorfunctionsofcarbohydrates,lipids,proteins,and nucleicacids.

2.05B.Explainhowenzymeswork.

KEYPOINTSTOEMPHASIZEWHENTEACHINGTHECHEMICALBASISOFLIFE

Relationshipbetweenstructureandfunction:

Thestructureofanatom,particularlyitsoutermostelectrons,determinesitschemicalbehavior.The electronarrangementdetermineswhetheranatomgainselectrons,loseselectrons,orshareselectrons. Atomsthatgainorloseelectronsformions(andionicbonds),andatomsthatshareelectronsform covalentbonds.Thetypeofbond,andhowmanybondseachatomforms,determinethestructureand futurereactivityofmolecules.Lifedependsonarelativelysmallnumberofdifferentelements,because onlythoseelementscanformstable,functionalmolecules.Itisalsoimportantforstudentstorecognize thestructure-functionrelationshipsforenzymesandotherproteinmolecules.Theshapeofprotein moleculesdeterminesandconstrainsthefunctionofthatprotein.Destroyingthatshape(denaturation) destroysthatfunction.Itisagoodideatospendabitoftimediscussingwhatdenaturingactuallydoesto theshapeofamoleculeandthereforetheavailabilityofactivesitesorbindingsitesforothermolecules. Studentshaveadifficulttimethinkingofmoleculesinthreedimensionssomodelsordemonstration aidesmaybenecessary.Theconceptofdenaturationshouldbestressedwhenyoudiscusstheactionsof enzymesandtheirregulation.Theideaofanoptimalrangeforeachenzymeisessentialto understandingmanyregulatorypathwayslateron.Additionally,youcanhighlightseveralgenetic disordersthathavetheirrootsinnon-functionalenzymes.Rememberthatstudentswithpoorerscience backgroundstendtohavetroubledevelopingmentalpicturesofthingsthatareassmallasatoms. Anythingthatyoucanbringintotheclassroomorlabthathelpsstudentsformrobustmentalimageswill behelpful.Onehastobecarefultopointoutthelimitationsofanyspecificthree-dimensionalmodelor simulation,however.

Homeostasis:

Theconceptofchemicalequilibriumis,initsessence,asimplerformationofthedynamicequilibrium establishedandmaintainedbyallofthebody'sprocesses.Helpstudentsexplorethesimilaritiesand differencesbetweenchemicalequilibriaandbiologicalhomeostasis.Oneofthekeyconceptsthatisoften overlookedinthisregardisthefactthatbiologicalorganismsareopensystems,sothemetaphorof chemicalequilibriumasanequivalentforhomeostasisquicklybreaksdown,sinceatruestablechemical equilibriumpresumesaclosedsystem.

Changethroughtime:

Thisisaharderthemetolinkspecificallytothischapter.Theeasiestlong-termchangeexamplesarein thecontextofhowthechemicalstructureofcompounds(collagenfibersinconnectivetissue)become alteredthroughtime(morecross-linking),andasaresultthepropertiesatthenextleveloforganization alsobecomealteredthroughtime(lessflexibility).Theshort-termchangesassociatedwithenergy transformationreactionsareveryimportant.Understandingoflaterprocesses,suchasthemechanismof musclecellcontraction,iseasierifstudentsarealreadyfamiliarwiththepivotalroleofATPinmediating thecellsability(orinability)toproduceaparticularchangeinfunctionataparticulartime.

Celltheoryandbiochemistry:

Asthefoundationallevelsofbiologicalorganization,thepivotalpositionofcellsandbiochemistryin understandinghigherlevelsoforganizationcannotbestressedtoostrongly.Thisverycentralityishard formanystudentstoappreciateandsoneedstobereinforcedinasmanyplacesaspossible.That

studentshavenotachievedthisfoundationalunderstandingmaybecomeapparentintheiranswersto questionsconcerningphysiologicalmechanismsofcontrolandcell-to-cellcommunication.Students shouldunderstandthatwithoutenzymes,many(ifnotmost)essentialchemicalreactionswouldnot occurfastenoughtosustainlife.Theyshouldalsounderstandthatenzymesdeterminewhichchemical reactionsoccurinacell;thisdeterminesacell's"occupation."Forexample,livercellsdo"liver"things becausetheir"liver"enzymesareactive.Itshouldbestressedagainthateverythingthathappensatthe organelle,cell,tissue,organ,organsystem,andorganismlevelisdeterminedbythethingsthathappenat thechemicallevel.Laterdiscussionsofmembranereceptorsandintracellularcommunicationallhave biochemicalbases.

CONTENTOUTLINE

Topic Page(s) Figures andTables

2.1BasicChemistry

A.Matter,mass,andweight

1.Definitionsofmatter,mass,andweight

2.Introductiontotheinternationalstandard

B.Elementsandatoms

C.Atomicstructure

1.Subatomicparticles

a.Nucleus

 Neutrons(neutral)

 Protons(positivecharge)

b.Electroncloud

Electrons(negativecharge)

2.Atomicnumber

3.Massnumber

D.Electronsandchemicalbonding

1.Ionicbonding

2.Covalentbonding

a.Single

b.Double

c. Polar

E.Hydrogenbonding

F.Moleculesandcompounds

G.Dissociation 21-26

ClinicalImpact:ClinicalUsesofAtomicParticles 28

2.2ChemicalReactions

A.Classificationofchemicalreactions

1.Synthesisreactions

2.Decompositionreactions

26-30

Table2.1p.22

Fig.2.1p.22

Fig.2.2p.23

Fig.2.3p.23

Table2.2p.24

Fig.2.4p.24

Fig.2.5p.25

Fig.2.6p.25

Table2.3p.25

Fig.2.7p.26

Fig.2.8p.29

3.Exchangereactions

B.Reversiblereactionsequilibrium

C.Energyandchemicalreactions (Fig.2.8,p.28)

2.Kineticenergy

3.Mechanicalenergy

4.Chemicalenergy

D.Rateofchemicalreactions

1.Reactants

2.Concentration

3.Temperature

4.Catalystsenzymes

2.2AcidsandBases

A.ThepHscale

1.Neutralsolution

2.Acidicsolution

3.Alkaline,orbasicsolution

B.Salts

C.Buffers

2.4.InorganicMolecules

A.Oxygenandcarbondioxide

B.Water

1.Properties

a.Stabilizesbodytemperatureabsorbsheat

b.Protectionlubricant

c. Chemicalreactions

30-31

d.Transportdissolveinwater 31

2.5OrganicMolecules

A.Carbohydrates

1.Monosaccharides

2.Disaccharides

3.Polysaccharides

B.Lipids

1.Fats(triglycerides)

a.Saturated

b.Unsaturated

i.Monounsaturated

ii.Polyunsaturated

2.Phospholipids

a.Hydrophobic

b.Hydrophilic

3.Eicosanoids

a.Prostaglandins

b.Thromboxanes

c. Leukotrienes

4.Steroids

C.Proteins

Fig.2.9p.30

Fig.2.10p.31

31-39

Table2.4p.32

Fig.2.11p.33

Fig.2.12p.34

Fig.2.13p.34

Fig.2.14p.35

Fig.2.15p.35

1.Aminoacids

2.Denaturation

3.Enzymes

a.Activationenergy

b.Enzymeaction

D.Nucleicacids

1.DNA

2.RNA

E.Adenosinetriphosphate

ACaseinPoint:

LearningOutcomesCorrelationwithQuestionTypes

Fig.2.16p.37

Fig.2.17p.38

Fig.2.18p.38

Fig.2.19p.38

Fig.2.20p.39

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