Neuromuscular Physiology: I-band, Neuron Structure, Muscle Contraction, and Fiber Types, Quizzes of Kinesiology

Download Neuromuscular Physiology: I-band, Neuron Structure, Muscle Contraction, and Fiber Types and more Quizzes Kinesiology in PDF only on Docsity! TERM 1 Sarcolemma DEFINITION 1 Muscle membranePlasmalemma (a plasma membrane that surrounds an individual muscle fiber)Basement membrane TERM 2 Sarcoplasm DEFINITION 2 A gelatin-like substance that fills the spaces within and between myofibrilsStores proteins, minerals, glycogen, fats, and organelles TERM 3 Transverse-Tubules (T-tubules) DEFINITION 3 Extensions of the plasmalemma that pass laterally through the muscle fiberConducts impulses to individual myofibrils TERM 4 Sarcoplasmic Reticulum DEFINITION 4 Membranous channels that parallel the myofibrils and loop around themStorage site for calcium TERM 5 Myofibril DEFINITION 5 Contractile elementMicrofilaments arranged in sarcomeres TERM 6 Structure of a Myofibril DEFINITION 6 Each muscle fiber contains 100's - 1000's of myofibrilsArrangement of microfilaments give the muscle characteristic striated appearanceComposed of actin and myosinArranged end-to-end at z-line TERM 7 Actin DEFINITION 7 Thin FilamentAttach at z-line (z-disks) TERM 8 Troponin DEFINITION 8 Wraps around the actin filament TERM 9 Tropomyosin DEFINITION 9 Globular protein attached to both actin and tropomysin TERM 10 Myosin DEFINITION 10 Thick filamentMyosin head has ATPace stored on it2 protein strands twisted together TERM 21 Action Potential DEFINITION 21 Dendrites receive a signal from the brain or spinal cordAP travels down the axon to the axon terminalsAcetylcholine (Ach) is releasedSpreads over the T-tubulesDepolarization continues down the muscle fiber TERM 22 Role of Ca++ in the Muscle Fiber DEFINITION 22 The AP through the T-tubules causes the SR to release Ca++ into the sarcoplasmWhen Ca++ is released, it bonds with troponin and moves tropomyosin off the myosin-binding sitesMyosin heads can then attach to the actin TERM 23 Sliding Filament Theory DEFINITION 23 A myosin cross-bridge attaches to an actin filament, and then the power stroke drags the two filaments past one anotherGoal is to make sarcomere shorten TERM 24 What does Muscular Contraction do to the BANDS? DEFINITION 24 I-band: DecreasesA-band: Stays the sameH-zone: DecreasesActin and Myosin: Do NOT change lengthSarcomeres: Shorten with contraction TERM 25 Sliding Filament Theory- Key Steps to Muscle Contraction DEFINITION 25 Neurotransmitter binds to receptor on sarcolemma, continuing APAP travels down T-tubule to SRSR releases Ca++ into sarcoplasmCa++ binds to troponin which pulls tropomyosin off binding sitesEnergized myosin heads attach to open actin binding sitesMyosin heads pull actin toward center of sarcomereATP will BIND to myosin head, releasing it from actinATPase breaks down ATP, re-energizing itRepeat until contraction is stopped TERM 26 Three Ways to Stop Muscular Contraction DEFINITION 26 Remove motor unit stimuli - Ca++ pumped back into SRRun out of ATPMaximal shortening - run out of binding sites TERM 27 Type I Fibers DEFINITION 27 High aerobic enduranceRecruited most often during low intensity endurance activities TERM 28 Type II Fibers DEFINITION 28 Better anaerobic enduranceGenerate more force, but fatigue quickerRecruited predominately for highly explosive events TERM 29 Distribution of Fiber Types DEFINITION 29 Not the same in all muscles of the bodyIn general, a person's arms and legs have similar fiber compositions TERM 30 Determination of Fiber Type DEFINITION 30 Relative composition of slow twitch and fast twitch fibers largely genetic and motor neuron innervation TERM 31 Fiber Type - Adaptations with training? DEFINITION 31 IIa --> IIx: Yes!Otherwise minimal TERM 32 Fiber Type - Changes with Aging? DEFINITION 32 Type II --> Type I: Yes TERM 33 Which Fiber type do Long Distance Runners predominately have? DEFINITION 33 Type IWorld class champions in the marathon reported to possess 93-99% Type I TERM 34 Principle of Orderly Recruitment DEFINITION 34 Motor units are ranked and used based on force productionSlow twitch then add fast twitch for graded amount TERM 35 Size Principle DEFINITION 35 May partially explain the principle of orderly recruitmentSmaller motor units are recruited first TERM 46 Optimal Sarcomere Length DEFINITION 46 The length where there is optimal overlap of actin and myosin TERM 47 Muscle Fiber and Sarcomere Length DEFINITION 47 Can generate maximal force with a slight pre- stretchDecreased force with stretched too far or contract too far TERM 48 Concentric Contractions DEFINITION 48 ShorteningSlower = more force TERM 49 Eccentric "contractions" DEFINITION 49 LengtheningFaster = more force TERM 50 Joint Angle DEFINITION 50 Relative position of tendon insertion to load will affect ability to produce forceEvery muscle has an individual "optimal" joint angle for maximum force production TERM 51 Central Nervous System DEFINITION 51 BrainSpinal cord TERM 52 Peripheral Nervous System DEFINITION 52 SomaticAutonomic TERM 53 Somatic DEFINITION 53 Sensory Division (afferent)Motor Division (efferent)Carries neural messages from spinal cord to skeletal muscle (for contraction to occur) TERM 54 Autonomic DEFINITION 54 SypatheticParasympatheticControls the body's involuntary internal functions TERM 55 Resting Membrane Potential DEFINITION 55 -70mv TERM 56 How is RMP maintained? DEFINITION 56 1. Membrane PermeabilityGreater permeability to K+ than Na+, thus K+ will flow with chemical gradient (OUT of cell)2. Sodium-Potassium Pump (Na+/K+ Pump)3 Na+ OUT of cell for every 2 K+ brought INTO cellCosts an ATP TERM 57 Polarizations DEFINITION 57 Changes in membrane permeability to Na+ TERM 58 Hyperpolarization DEFINITION 58 Becomes more negative TERM 59 Depolarization DEFINITION 59 Becomes less negativeWhat happens when an AP is sent TERM 60 Graded Potential DEFINITION 60 Dendrites and cell bodyLocalized changes in the membrane potentialChange of less than 15mV TERM 71 Golgi Tendon Organs (GTO) Location DEFINITION 71 In tendon TERM 72 GTO Resonds To DEFINITION 72 Tension/force TERM 73 GTO Produces DEFINITION 73 Antagonist Contraction TERM 74 GTO Mechanism DEFINITION 74 Inhibitory response TERM 75 GTO Prevents DEFINITION 75 Connective tissue injury TERM 76 Sensory- Motor Integration DEFINITION 76 The process by which the sensory and motor systems communicate and coordinate with each other TERM 77 Simple Motor Reflex DEFINITION 77 Sensory impulse terminates in the spinal cord TERM 78 Higher and More Complex Reactions DEFINITION 78 Sensory impulse terminates at higher levels in the brain TERM 79 Motor Reflex DEFINITION 79 A preprogrammed response TERM 80 Crossed Extensor Reflex DEFINITION 80 Flexors in the injured limb contract while the extensors relaxStep on glass TERM 81 Feedback inhibition DEFINITION 81 Inhibit one muscle while opposite muscle contracts TERM 82 Mechanoreceptors DEFINITION 82 Respond to mechanical forces TERM 83 Thermoreceptors DEFINITION 83 Respond to changes in temperature TERM 84 Nociceptors DEFINITION 84 Respond to painful stimuli TERM 85 Photoreceptors DEFINITION 85 Respond to light to allow vision TERM 96 Agility DEFINITION 96 A rapid, whole-body movement with change of velocity or direction in response to a stimulus TERM 97 Agility Assessment DEFINITION 97 Pro-agility (used in NFL combine) TERM 98 Speed and Acceleration DEFINITION 98 Speed of an object is the magnitude of its velocity (the rate of change of its position)Acceleration is the rate of change of velocity over time TERM 99 Sprinting Speed DEFINITION 99 The ability to run at maximal or near maximal efforts for relatively short period of time. TERM 100 Acceleration DEFINITION 100 Time taken to reach top speed (e.g., first 3 steps) TERM 101 Aerobic Power DEFINITION 101 Rate of energy release by cellular metabolic processes that depend upon the availability and utilization of oxygenVO2 max (directly measured or field test) TERM 102 Anaerobic Power DEFINITION 102 Rate of energy release by cellular metabolic processes that function without the utilization of oxygenMaximal capacity of anaerobic system to produce ATP TERM 103 Anaerobic Power Assessment DEFINITION 103 Wingate, etc (critical power) TERM 104 Resistance Training DEFINITION 104 A systematic program of exercises involving the exertion of force against a load used to develop strength, endurance, and/or hypertrophy of the muscular system TERM 105 Training DEFINITION 105 Progressive overload to displace homeostasis and create stimulus for adaptations --> improved performance TERM 106 Principles of Training DEFINITION 106 Training program must be systematic, consider the demands of the activity, and consider the needs, preference, and ability of the athleteA number of principles are followed to optimize training and athletic potential TERM 107 General Principles of Training DEFINITION 107 IndividualitySpecificityReversibilityProgressive OverloadHard/EasyMuscle BalancePeriodization TERM 108 Individuality DEFINITION 108 Consider the needs and abilities of individual athletes TERM 109 Specificity DEFINITION 109 Response is specific to the mode and intensity of exercise and the exact movement (fiber type/ muscle group/ energy system) TERM 110 Progressive Overload DEFINITION 110 A gradual increase in physical activity, working a muscle group or body system beyond accustomed levelsSystem gradually adapts, resulting in improved physiological functioningCan alter: Intensity/resistance, repetitions/sets, velocity of contraction