Chapter 38: Protection, Support, Movement: Skin, Skeleton, and Muscle

Fig. 40-11EpidermisDermisHypodermisAdipose tissueBlood vesselsHairSweatporeMuscleNerveSweatglandOil glandHair follicle

Fig. 50-25aBundle of muscle fibersMuscleSingle muscle fiber (cell)NucleiZ linesPlasma membraneMyofibrilSarcomere

Fig. 50-25bTEMThick filaments (myosin)M lineZ lineZ lineThin filaments (actin)Sarcomere0.5 m

Fig. 50-26ZRelaxed muscleM Z Fully contracted muscleContracting muscleSarcomere0.5 mContracted Sarcomere

Fig. 50-30Spinal cordMotor neuron cell bodyMotor neuron axonNerveMuscleMuscle fibersSynaptic terminalsTendonMotor unit 1Motor unit 2

Fig. 50-29SarcomereCa2+ ATPase pump Ca2+ released from SRSynaptic terminalT tubuleMotor neuron axonPlasma membrane of muscle fiberSarcoplasmic reticulum (SR)MyofibrilSynaptic terminal of motor neuronMitochondrionSynaptic cleftT TubulePlasma membraneCa2+Ca2+CYTOSOLSRATPADPP iACh

Fig. 50-27-4Thin filamentsATP Myosin head (low- energy configurationThick filamentThin filamentThick filamentActinMyosin head (high- energy configurationMyosin binding sitesADPP iCross-bridgeADPP iMyosin head (low- energy configurationThin filament moves toward center of sarcomere.ATP ADPP i+

Fig. 50-28Myosin- binding siteTropomyosin(a) Myosin-binding sites blocked(b) Myosin-binding sites exposedCa2+Ca2+-binding sitesTroponin complexActin

Fig. 50-31Summation of two twitchesTetanusSingle twitchTimeTensionPair of action potentialsAction potentialSeries of action potentials at high frequency

Fig. 40-5kSkeletal muscleMultiplenucleiMuscle fiberSarcomere100 m

Fig. 40-5lSmooth muscleNucleusMusclefibers25 m

Fig. 40-5mNucleusIntercalateddiskCardiac muscle50 m

*Figure 40.11 Mammalian integumentary system*Figure 50.25 The structure of skeletal muscle

*Figure 50.25 The structure of skeletal muscle

*Figure 50.26 The sliding-filament model of muscle contractionFor the Cell Biology Video Conformational Changes in Calmodulin, go to Animation and Video Files.For the Cell Biology Video Cardiac Muscle Contraction, go to Animation and Video Files.

*Figure 50.30 Motor units in a vertebrate skeletal muscle*Figure 50.29 The regulation of skeletal muscle contraction*Figure 50.27 Myosin-actin interactions underlying muscle fiber contraction

*Figure 50.28 The role of regulatory proteins and calcium in muscle fiber contraction*Figure 50.31 Summation of twitches*Figure 40.5 Structure and function in animal tissues*Figure 40.5 Structure and function in animal tissues*Figure 40.5 Structure and function in animal tissues