Term
|
Definition
| plasma membrane of muscle fiber |
|
|
Term
| plasma membrane of muscle fiber |
|
Definition
|
|
Term
|
Definition
| contains microfilaments; 100s to 1000s of myofibrils per one muscle fiber; z lines / a bands / h zones / i bands / m lines |
|
|
Term
|
Definition
|
|
Term
|
Definition
| functional unit of skeletal muscle; extends from z line to z line |
|
|
Term
| functional unit of skeletal muscle; extends from z line to z line |
|
Definition
|
|
Term
|
Definition
| between thick filaments; anchor for thin filaments |
|
|
Term
|
Definition
| bands of thick filaments (myosin); give muscle fibers their striated appearance |
|
|
Term
|
Definition
| areas of thick filaments where no thin filaments overlap |
|
|
Term
| areas of thick filaments where no thin filaments overlap |
|
Definition
|
|
Term
| line between thick filaments that anchors thin filaments |
|
Definition
|
|
Term
| bands of thick filaments that give the muscle fiber its striated appearance |
|
Definition
|
|
Term
|
Definition
| area of thin filaments where no thick filaments overlap; does not completely contain the thin filaments though |
|
|
Term
| area of thin filaments where no thick filaments overlap |
|
Definition
|
|
Term
|
Definition
| lines between thin filaments that anchor thick filaments |
|
|
Term
| lines between thin filaments that anchor thick filaments |
|
Definition
|
|
Term
| electrochemical equilibrium for a muscle fiber |
|
Definition
| -85 mV; resting potential |
|
|
Term
|
Definition
| cell going towards a more positive voltage |
|
|
Term
|
Definition
| always open; leaky channels; specific to an ion **? |
|
|
Term
|
Definition
| synaptic knob + motor end plate |
|
|
Term
| channels in motor end plate |
|
Definition
| Na+ chemically regulated channels |
|
|
Term
| channels in motor neuron axon (pre-synapse) |
|
Definition
| Ca++ voltage regulated channels |
|
|
Term
|
Definition
| invagination of the sarcolemma on a muscle fiber where 80% of the Ca++ that drives muscle contraction comes from |
|
|
Term
| invagination of the sarcolemma |
|
Definition
|
|
Term
| 80% of the Ca++ that drives muscle contraction comes from |
|
Definition
| T-tubule/ invagination in the sarcolemma |
|
|
Term
| 20% of the Ca++ that drives muscle contraction comes from |
|
Definition
|
|
Term
| drives muscle contraction |
|
Definition
| influx of Ca++ into the muscle fiber |
|
|
Term
|
Definition
| acetylcholine; neurotransmitter found within the synaptic vesicles in the synaptic knob |
|
|
Term
|
Definition
| 1. stimulus 2. voltage regulated channels allow Ca++ into neuron from extracellular space [Ca++ ions rupture the synaptic vesicles, releasing ACH into the neuromuscular junction] 3. chemically regulated channels allow Na+ into the muscle fiber, causing the charge of the muscle fiber to become more + 4. voltage regulated channels on the sarcolemma & terminal cisterna allow Ca++ into the muscle fiber 5. contraction |
|
|
Term
|
Definition
| thin filaments of muscle fiber; looks like a double strand of pearls; troponin & tropomyosin |
|
|
Term
| thin filaments of muscle fiber |
|
Definition
|
|
Term
|
Definition
| large protein molecules at the ends of actin |
|
|
Term
| large protein molecules at the ends of actin |
|
Definition
|
|
Term
|
Definition
| rod-shaped protein that spirals around actin & blocks myosin binding sites to prevent contraction (actin condom) |
|
|
Term
|
Definition
|
|
Term
| rod-shaped protein that spirals around actin & blocks myosin binding sites to prevent contraction |
|
Definition
|
|
Term
|
Definition
| when exposed, myosin binds to actin at myosin binding sites to cause contraction |
|
|
Term
|
Definition
| thick filaments of muscle fiber; myosin heads + cross bridge |
|
|
Term
|
Definition
| contain ATP; double golf club shape; high energy configuration & low energy configuration |
|
|
Term
| part of myosin that contains ATP |
|
Definition
|
|
Term
|
Definition
| formed by myosin heads attaching to actin @ myosin binding sites |
|
|
Term
|
Definition
| increase intracellular Ca++ |
|
|
Term
|
Definition
| moves tropomyosin away from myosin binding sites |
|
|
Term
| moves tropomyosin away from myosin binding sites |
|
Definition
|
|
Term
| high energy configuration of myosin heads |
|
Definition
| myosin heads are "erect" in"cocked position" |
|
|
Term
| low energy configuration of myosin heads |
|
Definition
| myosin heads are not erect |
|
|
Term
|
Definition
| process of myosin heads attaching, detaching, and reattaching farther down the actin filament; several power strokes |
|
|
Term
|
Definition
|
|
Term
| process of myosin heads attaching, detaching, and reattaching farther down on the actin filament |
|
Definition
|
|
Term
|
Definition
| going from high energy configuration to low energy configuration |
|
|
Term
|
Definition
| 1. when cross bridges form, they act as ATPase (splits ATP for use as energy) 2. myosin head moves to the low energy position, then binds a new ATP & detaches from actin 3. returns to the high energy configuration w/ new cross bridges farther down the actin strand 4. ratcheting continues until intracellular Ca++ levels are back down |
|
|
Term
|
Definition
| short-term energy fix; 1. myosin heads (which store ATP) give a few seconds of contraction 2. creatine phosphate (storage molecule for ATP in muscles) gives about 30 seconds of contraction 3. glycogen (storage form of glucose) gives about 60 seconds of contraction |
|
|
Term
| myosin heads in anaerobic metabolism |
|
Definition
| give a few seconds of contraction |
|
|
Term
| creatine phosphate in anaerobic metabolism |
|
Definition
| give about 30 seconds of contraction |
|
|
Term
|
Definition
| storage form of glucose, gives about 60 seconds of contraction. 1 ATP from breaking glycogen into glucose; 2 ATP from breaking glucose into pyruvic acid via glycolysis |
|
|
Term
|
Definition
| produces 2 ATP for anaerobic metabolism; breaking glucose into pyruvic acid |
|
|
Term
|
Definition
| long-term energy fix; O2 required to run the Krebs cycle, which generates 32 ATP (hours of energy) |
|
|
Term
|
Definition
| shows how crossbridges are run by ATP; dying cells can't get rid of calcium/ keep forming crossbridges, so the more calcium in the muscles, the more stiff they become; ends when proteins of the body finally break down the crossbridges; 1. muscles stiffen 3-4 hours after death 2. peak of rigidity occurs 12 hours after death 3. gradually dissipates over next 48-60 hours (2-2.5 days) |
|
|
Term
| peak of rigidity in rigor mortis |
|
Definition
|
|
Term
| muscles stiffen _____ hours post mortem |
|
Definition
|
|
Term
| rigor mortis dissipates after _______ hours |
|
Definition
| 48-60 when body proteins break down the cross bridges |
|
|
Term
|
Definition
| buildup of lactic acid, & pyruvate & O2 are needed to start the Krebs cycle; lactic acid pools in the muscles & causes muscle fatigue & cramps |
|
|
Term
|
Definition
|
|
Term
|
Definition
| slow-twitch // caribou // smaller in diameter than Type II & III; lots of mitochondria to produce ATP; red, because they have the pigment myoglobin that binds O2; resistant to muscle fatigue; big part of aerobic metabilism; marathon runners |
|
|
Term
| slow twitch muscle fibers |
|
Definition
| caribou; type I; smaller in diameter than Type II & III; lots of mitochondria to produce ATP; red, because they have the pigment myoglobin that binds O2; resistant to muscle fatigue; big part of aerobic metabilism; marathon runners |
|
|
Term
|
Definition
| type I; slow twitch; smaller in diameter than Type II & III; lots of mitochondria to produce ATP; red, because they have the pigment myoglobin that binds O2; resistant to muscle fatigue; big part of aerobic metabilism; marathon runners |
|
|
Term
| muscle fiber type w/ most mitochondria |
|
Definition
| type I // caribou // slow twitch |
|
|
Term
| muscle fiber type w/ the smallest diameter |
|
Definition
| type I // caribou // slow twitch |
|
|
Term
| muscle fiber type most resistant to fatigue |
|
Definition
| type I // caribou // slow twitch |
|
|
Term
| muscle fiber type w/ myoglobin |
|
Definition
| type I // caribou // slow twitch; myoglobin is a pigment that makes the muscle fiber appear red & binds O2 |
|
|
Term
|
Definition
| red pigment in muscle fibers (most in type I fibers) that binds O2 |
|
|
Term
| muscle fiber type predominant in aerobic metabolism |
|
Definition
| type I // caribou // slow twitch |
|
|
Term
|
Definition
| fast-twitch // cheetah // larger in diameter than type I fibers; fewer mitochondria to make ATP than type I fibers; white in color (little to no myoglobin); fatigue easily; anaerobic metabolism; body builders & sprinters |
|
|
Term
|
Definition
| type II // fast-twitch // larger in diameter than type I fibers; fewer mitochondria to make ATP than type I fibers; white in color (little to no myoglobin); fatigue easily; anaerobic metabolism; body builders & sprinters |
|
|
Term
| fast-twitch muscle fibers |
|
Definition
| type II // cheetah // larger in diameter than type I fibers; fewer mitochondria to make ATP than type I fibers; white in color (little to no myoglobin); fatigue easily; anaerobic metabolism; body builders & sprinters |
|
|
Term
| muscle fiber type with larger diameter |
|
Definition
| type II // cheetah // fast-twitch |
|
|
Term
| muscle fiber type with fewer mitochondria |
|
Definition
| type II // cheetah // fast-twitch |
|
|
Term
| muscle fiber type that is white in color (little to no myoglobin) |
|
Definition
| type II // cheetah // fast-twitch |
|
|
Term
| muscle fiber type that fatigues easily |
|
Definition
| type II // cheetah // fast-twitch |
|
|
Term
| muscle fiber type involved in anaerobic metabolism |
|
Definition
| type II // cheetah // fast-twitch |
|
|
Term
|
Definition
| intermediate twitch fibers // wolf // type II fibers that have been trained to be like type I; whitish to pink; more mitochondria than type II but less than type I; more glycolytic enzymes than type II; more resistant to fatigue than type II |
|
|
Term
|
Definition
| type III // intermediate twitch // type II fibers that have been trained to be like type I; whitish to pink; more mitochondria than type II but less than type I; more glycolytic enzymes than type II; more resistant to fatigue than type II |
|
|
Term
| intermediate twitch muscle fibers |
|
Definition
| type III // wolf // type II fibers that have been trained to be like type I; whitish to pink; more mitochondria than type II but less than type I; more glycolytic enzymes than type II; more resistant to fatigue than type II |
|
|
Term
| muscle fiber type that looks whitish to pink |
|
Definition
| type III // wolf // intermediate twitch |
|
|
Term
| most mitochondria: middle : least mitochondria |
|
Definition
| type I : type III : type II |
|
|
Term
| muscle fiber type with more glyocolytic enzymes (anaerobic metabolism) |
|
Definition
|
|
Term
|
Definition
| motor neuron + all the muscle fibers it innervates |
|
|
Term
|
Definition
| the response of a single motor unit to a single action potential of its motor neuron; latent phase + contraction + relaxation |
|
|
Term
| latent phase of muscle twitch |
|
Definition
| stimulus has been received by motor unit, but before the response; only lasts a few milliseconds |
|
|
Term
| contraction phase of muscle twitch |
|
Definition
| muscle creates a positive response as the muscle contracts (shortens); only lasts 10-100 milliseconds |
|
|
Term
|
Definition
| muscle fibers relax & return to baseline, lasts 10-100 milliseconds |
|
|
Term
| muscle twitch: graded response, or all or none? |
|
Definition
| ALL OR NONE: if you don't shock the motor unit hard enough, it will stay at baseline. if you shock it more than enough, it still will not exceed max contraction (but an entire muscle can have a graded response) |
|
|
Term
| 2 ways to have a graded response in a muscle |
|
Definition
| motor unit summation/recruitment/increasing stimulus & wave summation/ increasing frequency of stimulus until tetany is achieved |
|
|
Term
|
Definition
| "recruitment" // increasing the number of motor units to be stimulated until all are stimulated & max contraction occurs. (increasing the strength of the stimulus) |
|
|
Term
|
Definition
| increasing the frequency of the stimulus until all motor units are stimulated/ tetany is achieved |
|
|
Term
|
Definition
| smooth, sustained contraction resulting from a high frequency stimulation (wave summation) |
|
|
Term
|
Definition
| anomaly in mammals; graded muscle response, even with unchanging frequency & strength of stimulus; ONLY happens when muscles haven't warmed up |
|
|
