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HumanBiology C 1 HAPTER Human Biology CHAPTER OUTLINE 1.1 OrganizationoftheHumanBody 1.2 Homeostasis 1.3 Skin 1.4 NailsandHair 1.5 KeepingSkinHealthy 1.6 HumanSkeletalSystem 1.7 SkeletalSystemJoints 1.8 KeepingBonesandJointsHealthy 1.9 Smooth,Skeletal,andCardiacMuscles 1.10 Muscles,Bones,andMovement 1.11 MusclesandExercise 1.12 FoodandNutrients 1.13 TypesofNutrients 1.14 VitaminsandMinerals 1.15 ChoosingHealthyFoods 1.16 HumanDigestiveSystem 1.17 EnzymesintheDigestiveSystem 1.18 DigestiveSystemOrgans 1.19 BacteriaintheDigestiveSystem 1.20 HealthoftheDigestiveSystem 1.21 CardiovascularSystem 1.22 CirculationandtheLymphaticSystem 1.23 Heart 1.24 BloodVessels 1.25 ComponentsofBlood 1.26 BloodTypes 1.27 BloodDiseases 1.28 BloodPressure 1.29 CardiovascularDiseases 1.30 CardiovascularSystemHealth 1.31 Respiration 1.32 RespiratorySystemOrgans 1.33 ProcessesofBreathing 1 www.ck12.org 1.34 RespiratorySystemDiseases 1.35 RespiratorySystemHealth 1.36 Excretion 1.37 UrinarySystem 1.38 Kidneys 1.39 ExcretorySystemProblems 1.40 NervousSystem 1.41 NerveCellsandNerveImpulses 1.42 CentralNervousSystem 1.43 PeripheralNervousSystem 1.44 HumanVision 1.45 HowtheEyeWorks 1.46 VisionCorrection 1.47 HearingandBalance 1.48 Touch 1.49 TasteandSmell 1.50 DiseasesoftheNervousSystem 1.51 InjuriesoftheNervousSystem 1.52 KeepingtheNervousSystemHealthy 1.53 Pathogens 1.54 HIVandAIDS 1.55 PreventingInfectiousDiseases 1.56 Cancer 1.57 Diabetes 1.58 AutoimmuneDiseases 1.59 PreventingNoninfectiousDiseases 1.60 BarrierstoPathogens 1.61 InflammatoryResponse 1.62 LymphaticSystem 1.63 BandTCellResponse 1.64 Immunity 1.65 MaleReproductiveSystem 1.66 MaleReproductiveStructures 1.67 HumanSperm 1.68 FemaleReproductiveSystem 1.69 FemaleReproductiveStructures 1.70 HumanEggCells 2 www.ck12.org Chapter1. HumanBiology 1.71 MenstrualCycle 1.72 Fertilization 1.73 PregnancyandChildbirth 1.74 InfancyandChildhood 1.75 PubertyandAdolescence 1.76 AdulthoodandAging 1.77 SexuallyTransmittedInfections 1.78 Non-InfectiousReproductiveSystemDisorders 1.79 ReproductiveSystemHealth 1.80 References Introduction Human Biology provides an overview of the physiology of humans, from the skin inward. In addition to the skin, theskeletal,muscular,nervous,circulatory,respiratory,digestive,excretory,immune,andreproductivesystemsare described. 3 1.1. OrganizationoftheHumanBody www.ck12.org 1.1 Organization of the Human Body • Listthelevelsoforganizationinthehumanbody. • Identifythefourtypesoftissuesthatmakeupthebody. Docellsworktogether? Cells, like these nerve cells, do not work in isolation. To send orders from your brain to your legs, for example, signalspassthroughmanynervecells. Thesecellsworktogethertoperformasimilarfunction. Justasmusclecells worktogether,bonecellsandmanyothercellsdoaswell. Agroupofsimilarcellsthatworktogetherisknownasa tissue. 4 www.ck12.org Chapter1. HumanBiology OrganizationofYourBody: Cells,Tissues,Organs Cells are grouped together to carry out specific functions. A group of cells that work together form a tissue. Your body has four main types of tissues, as do the bodies of other animals. These tissues make up all structures and contentsofyourbody. Anexampleofeachtissuetypeispicturedbelow(Figure1.1). FIGURE1.1 Yourbodyhasfourmaintypesoftissue: nervoustissue,epithelialtissue,connectivetissue,andmuscletissue. Theyarefoundthroughoutyourbody. 1. Epithelial tissue is made up of layers of tightly packed cells that line the surfaces of the body. Examples of epithelialtissueincludetheskin,theliningofthemouthandnose,andtheliningofthedigestivesystem. 2. Connectivetissueismadeupofmanydifferenttypesofcellsthatareallinvolvedinsupportingandbinding other tissues of the body. Examples include tendon, cartilage, and bone. Blood is also classified as a specializedconnectivetissue. 3. Muscletissueismadeupofbandsofcellsthatcontractandallowmovement. 4. Nervous tissue is made up of nerve cells that sense stimuli and transmit signals. Nervous tissue is found in nerves,thespinalcord,andthebrain. GroupsofTissuesFormOrgans A single tissue alone cannot do all the jobs that are needed to keep you alive and healthy. Two or more tissues working together can do a lot more. An organ is a structure made of two or more tissues that work together. The heart(Figure1.2)ismadeupofthefourtypesoftissues. 5 1.1. OrganizationoftheHumanBody www.ck12.org FIGURE1.2 The four different tissue types work to- getherintheheartastheydointheother organs. GroupsofOrgansFormOrganSystems Yourheartpumpsbloodaroundyourbody. Buthowdoesyourheartgetbloodtoandfromeverycellinyourbody? Yourheartisconnectedtobloodvesselssuchasveinsandarteries. Organsthatworktogetherformanorgansystem. Together,yourheart,blood,andbloodvesselsformyourcardiovascularsystem. Whatotherorgansystemscanyouthinkof? OrganSystemsWorkTogether Your body’s 12 organ systems are shown below (Table 1.1). Your organ systems do not work alone in your body. Theymustallbeabletoworktogether. Forexample,oneofthemostimportantfunctionsoforgansystemsistoprovidecellswithoxygenandnutrientsand to remove toxic waste products such as carbon dioxide. A number of organ systems, including the cardiovascular andrespiratorysystems,allworktogethertodothis. TABLE 1.1: MajorOrganSystemsoftheHumanBody OrganSystem MajorTissuesandOrgans Function Cardiovascular Heart;bloodvessels;blood Transports oxygen, hormones, and nutrients to the body cells. Moves wastes and carbon dioxide away fromcells. Lymphatic Lymphnodes;lymphvessels Defend against infection and dis- ease, moves lymph between tissues andthebloodstream. Digestive Esophagus; stomach; small intes- Digestsfoodsandabsorbsnutrients, tine;largeintestine minerals,vitamins,andwater. Endocrine Pituitary gland, hypothalamus; Produces hormones that communi- adrenalglands;ovaries;testes catebetweencells. 6 www.ck12.org Chapter1. HumanBiology TABLE 1.1: (continued) OrganSystem MajorTissuesandOrgans Function Integumentary Skin,hair,nails Providesprotectionfrominjuryand waterloss,physicaldefenseagainst infection by microorganisms, and temperaturecontrol. Muscular Cardiac (heart) muscle; skeletal Involvedinmovementandheatpro- muscle;smoothmuscle;tendons duction. Nervous Brain,spinalcord;nerves Collects, transfers, and processes information. Reproductive Female: uterus; vagina; fallopian Produces gametes (sex cells) and tubes; ovaries Male: penis; testes; sexhormones. seminalvesicles Respiratory Trachea,larynx,pharynx,lungs Brings air to sites where gas ex- changecanoccurbetweentheblood and cells (around body) or blood andair(lungs). Skeletal Bones,cartilage;ligaments Supportsandprotectssofttissuesof body; produces blood cells; stores minerals. Urinary Kidneys;urinarybladder Removes extra water, salts, and waste products from blood and body; controls pH; controls water andsaltbalance. Immune Bone marrow; spleen; white blood Defendsagainstdiseases. cells Vocabulary • cardiovascularsystem: Organsystemmadeupoftheheart,blood,andbloodvessels. • cells: Basicunitofstructureandfunctionofalivingorganism;thebasicunitoflife. • connectivetissue: Groupofcellsthatareallinvolvedinsupportingandbindingothertissuesofthebody;i.e. tendon,cartilage,bone,andblood. • epithelialtissue: Layersoftightlypackedcellsthatlinethesurfacesofthebody. • muscletissue: Bandsofcellsthatcontractandallowmovement. • nervoustissue: Groupofnervecellsthatsensestimuliandtransmitsignals; foundinbrain, spinalcord, and nerves. • organ: Structuremadeoftwoormoretissuesthatworktogether. • organsystem: Organsthatworktogethertoserveacommonpurpose. • tissue: Groupofsimilarcellsworkingtogether. Summary • Thelevelsoforganizationinthehumanbodyinclude: cells,tissues,organs,andorgansystems. • Therearefourtissuetypesinthebody: epithelialtissue,connectivetissue,muscletissue,andnervoustissue. Practice Usetheresourcesbelowtoanswerthefollowingquestions. 7 1.1. OrganizationoftheHumanBody www.ck12.org • HumanBodyPlanathttp://vimeo.com/37349968(2:28) MEDIA Clickimagetotheleftformorecontent. 1. Whatkindofsymmetrydoesthehumanbodyplanshow? Explainfullywhatthismeans. 2. Howdoesthissymmetryextendtooursenses? 3. Howmuchofourbodyismadeofmuscle? Whatdoesthismuscleallowustodo? 4. Howareoxygenandnutrientsdeliveredtothecellsofthebody? Goheretoseetheplacementofsomeorgansandbodyparts. Seehowfastyoucanassemblethesystems. • AllSystemsGoathttp://sciencenetlinks.com/interactives/systems.html Review 1. Whatarethefourlevelsoforganizationinanorganism? 2. Listthefourtypesoftissuesthatmakeupthehumanbody. 8