Complete List of Terms and Definitions for Nine - Muscle Tissue

Terms Definitions
sacroplasm cytoplasm
epimysium aka... superficial fasciae
origin less movable attachment
sarcoplasm muscle cell's cytoplasm
 
contains many mitochondria and specialized SER called Sarcoplasmic Reticulum
 
contains Myoglobin; Oxygen binding pigment in muscle similar to Hemoglobin
(1) binds to troponin Ca2+
Cardiac muscle characteristics striated, involuntary,auto-rhythmic,uninucleated(small amount are binucleated), found in myocardium, fibers are y branched
endomysium delicate connective tissue that surrounds individual skeletal muscle cells or fibers and loosely connects with adjacent muscle fibers
 
flexible elastic network contains capillaries and myosatellite cells
tendon to stretch out
 
continuation of three layers of ct covering muscle attatching to bone
 
 
Fascicle Spindle shaped with central belly
(1) diffuses from the cell K+
The sliding filament mechanism muscle contraction
fusiform shape wide middle tapered ends
Relaxation phase Relaxation phase: Ca levels fall,active site covered, cross-bridges detach,tension falls
 
myogram line has downward slope
Fibromyalgia -A group of signs and symptoms:
-chronic soft tissue pain
-Often comorbid with:
-Chronic Fatigue
-IBS
-Migraines 
-Sleep disorders
 
-Affects 2-3% of US, 85-90% women
-incidences increase with age
 
Satellite cells unspecialized myoblasts between the muscle fiber and endomysium
Nucleus The cellular structure that contains the genetic material of the cell
infoldings of sarcolemma of smooth muscle caveloae
NAMEis thier ability to transform chemical energy into directed mechanical energy muscles
NAME PROTIENhas two globular heads and a rodlike tail myosin
Muscle cell (fiber) or myofiber muscle fiber
, the endomysium-wrapped muscle fibers are grouped into ____ fascicles
structural organization of skeletal muscles small to big(6)(look at pic for this too)pg 44 myofilament(molecule), myofibril(organelle), muscle fiber(Cell),Fascicle(tissue), muscle, muscle group
muscle tissue comprises about ___% of total body mass on average 30-50%
Rhabyonyolitis Stems from trauma of muscle wasting diseases, leads to jaundice(i.e. crush injuries)
fatigue when muscles run out of oxygen
rising lactic levels lower tissue pH levels then muscles can no longer function normally
 
muscles needs enough energy supplysupplies,blood flow, normal oxygen levels,and normall pH levels
General characteristics of:
 
Cardiac Muscle 		myofibrils  in sacromeres like skeletal muscle
striated like skeletal muscle
relatively small cell size
single cental nucleus like smooth muscle
joined to intercalated discs at Zlines to give strength and stability
contracts w/o neural stimulation:automaticity
Triad membranes of 2 SR's + T Tubule
Myosin Protein that makes up a thick filament. Each myosin molecuole has a rod-like tail and two globular heads
A fascicle is surrounded by what connective tissue? Perimysium
Slow Twitch I slow oxidative fibers32-36 ATP formed.aerobic.red in color.endurance activities.
NAMEis a protien that makes up elastic filament titin
Each muscle fiber contain a large number of rodlike (1) that run parellel to its length myofibrils
Structural proteins Not as abundant as contractile proteins (actin or myosin) for alignment, stability, elasticity, extensibility etc. of myofibrils
a fine sheath of connective tissue consisting of areolar and reticular fibers-surrounds each individual muscle fiber Endomysium
Skeletal Muscle Packed by connective tissue sheets into organs which are attached to the skeleton. These muscles are voluntarily controlled.
Muscle Relaxation 1. Stimulus stops. 2.SACh is destroyed by AchEsterase or diffuses throughout the synaptic cleft. Membrane is no longer permeable to Na+. ACh also diffuses away.3.Ca2+ transported (active, ATP used) back into the sarcoplasmic reticulum.4.17. Low [Ca2+] in sarcoplasm causes Ca2+ to leave the troponin. 5.The tropomyosin shifts around to cover the myosin binding sites. The sarcomere will lengthen as the filaments slide back to their original position.
Aerobic Respiration Mitochondria use glucose and oxygen to produce CO2, H2O, and ATP:
1 C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + 32-36 ATP Glycogen stored in muscle provides glucose and myoglobin provides oxygen. Produces energy for regular activities. Sudden intense activity uses up all the oxygen more quickly than it is replaced. Takes time for respiratory/cardiovascular systems to respond to need for oxygen. Resting muscles have enough ATP for a few seconds of intense activity.
cross bridge when myosin heads interact with thin filaments of actin during a contraction only in the presence of calcium
 
What types of striated muscle are there? skeletal, cardiac
Muscle Tone The nearly constant state of low-level tension and resistance to stretch in a muscle
contracture cramping because lack of ATP does not allow crossbridge to detach.
What is a troponin? is a 3 polypeptide complex
NAMEonce this is generated it is propagated along the sacrolemma, it travels down the T tubules, and triggers Ca2+ release from the terminal cisternae action potential
what are the 2 types of muscle attachments? 

•Directly—epimysium
of muscle is fused to the periosteum
of bone or perichondrium of cartilage

•Indirectly—connective
tissue wrappings extend beyond the muscle as a ropelike tendon or sheetlike
aponeurosis






Although the axon terminal and the muscle fiber are exceedingly close (1–2 nm apart), they remain separated by a space, the __ ___ synaptic cleft
Effect of Exercise on Muscles .exercise increases muscle size, strength, and endurance. aerobic(endurance) exercise results in stronger, more flexible muscles with greater resistance to faigue - makes body metablism more efficient - improves digestion, coordination.Resistance( isometric exercise (weight lifting) increase muscle size and strength
Neuromuscular Junction The synapse between a nerve fiber and a muscle fiber.
Motor Unit A neuron and the muscle cell it supplies
voltage gated calcium channels @synaptic cleft where calcium entry triggers release of Ach
What is hemoglobin? is a pigment that transports oxygen in the blood
At each A band–I band junction, the sarcolemma of the muscle cell penetrates into the cell interior, forming an elongated tube called the _ ____ T tubule
process of contraction is powered and triggered by ATP, calcium ion
Polarized A cell at rest, waiting to react to a stimulus
3 Types of Muscle Cell Slow Oxidative (SO)
Half of the fibers of most muscles
Resist fatigue, capable of prolonged contraction
Highest in postural muscles
Generate ATP through aerobic respiration
 
Fast Oxidative-glycolytic (FOG)
Contract and relax more quickly than SO fibers
Generate ATP both aerobically and anaerobically
 
Fast Glycolitic (FG)
Largest, most powerful and fastest
Mainly anaerobic generation of ATP
Even as muscles pull on bones to cause movments, they (1) and (2) the joints of the skeleton stabilze and strengthen
Define Period of contraction. The period of contraction is when cross bridges are active, from the onset to the peak of tension development, and the myogram tracing rises to a peak. This period lasts 10–100 ms. If the tension (pull) becomes great enough to overcome the resistance of a load, the muscle shortens.
Describe steps of sliding filament model Nerve impulse transmits to cell interior of fiber by T-tubule

Ca ions release from terminal sac and enter sarcoplasm
Ca binds to troponin, causing transformational change
Change in troponin cause tropomyosin to move to reveal active sites


ATP hydrolysis to ADP + Pi (requires Mg)
Myosin bends while attached to actin
ATP binds to myosin, and myosin detach from actin
What are two sets of intrcellular tubules that make up skeletal muscle fibers? (2) (1)the SR (2) T tubules
Steps for Excitation, Coupling, Contraction, & Relaxation 1) signal in the neuron causes release of ACh into the synaptic cleft2) ACh binds to receptors at the motor end plate of the muscle fiberACh receptors are ligand-gated Na+ channels that open when ACh binds3) Na+ rushes into the cellcauses change in membrane potential right at the NMJ4) change in membrane potential opens voltage-gated ion channelslets Na+ in and K+ out and changes the membrane potential near the NMJopens more voltage-gated ion channels, changes potential a further from NMJpositive feedback mechanism continues to open more channels, cause more change5) results in an action potentialopening of channels and change in membrane potential is positive feedback mechanismspreads along the entire sarcolemmanow the muscle is excited, how does this cause muscle contraction?Excitation-contraction coupling:6) action potential spreads along sarcolemma and down the T tubules7) opens voltage-gated calcium channel in the T tubules8) opens ryanodine receptors in sarcoplasmic reticulumryanodine receptors are calcium channels connected to T tubule channelswhen T tubule channels are activated, ryanodine receptors openreleases lots of calcium into the sarcoplasm9) calcium binds to troponin10) tropomyosin moves off the active sites on the actin filaments so myosin can bindContraction:11) myosin hydrolyzes ATP and takes high-energy extended shape (reach)12) high-energy myosin binds to actin (grab)13) myosin returns to the low energy state and pulls actin with it (pull)14) myosin binds to new ATP – causes it to releases the actin (release)15) steps 11-14 repeat until signal to contract stops (or ATP is gone)Relaxation:16) neuron stops releasing ACh17) ACh in synaptic cleft is broken down by acetylcholinesterase18) Na+/K+ pump returns muscle fiber to resting membrane potential19) calcium is pumped back into the sarcoplasmic reticulum20) tropomyosin moves back over the actin active sites21) titin pushes sarcomeres back to original length
How is the ionic concentration of the resting state restored? by the Na K pump
What is a direct muscle attachment? is when the epimysium of the muscle is fused to the periosteum of the bone or perichondrium of the cartilage
In general, muscle contraction can be graded in two ways. Name them. (1) by changing the frequency of stimulation and (2) by changing the strength of the stimulus.
Titin has two basic fxns, what are they? (1) holding the thick filaments in place, thus maintaining the organization of the A band, and (2) assisting the muscle cell to spring back into shape after being stretched or shortening.