why do you think the details of skeletal muscle and cardiac muscle contraction.......?
913423
Because smooth muscle is only present in viscera and blood vessels, and is small, yet skeletal muscle is large and present throughout the body, therefore can be studied noninvasively.
676104
"The muscle fibers making up the single-unit muscle are gathered into dense sheets or bands. Though the fibers run roughly parallel, they are densely and irregularly packed together, most often so that the narrower portion of one fiber lies against the wider portion of its neighbor. These fibers have connections, the plasma membranes of two neighboring fibers form gap junctions that act as low resistance pathway for the rapid spread of electrical signals throughout the tissue. The multi-unit smooth muscle fibers have no interconnecting bridges. They are mingled with connective tissue fibers."\n\n"Smooth muscle is primarily under the control of autonomic nervous system, whereas skeletal muscle is under the control of the somatic nervous system. The single-unit smooth muscle has pacemaker regions where contractions are spontaneously and rhythmically generated. The fibers contract in unison, that is the single unit of smooth muscle is syncytial. The fibers of multi-unit smooth muscle are innervated by sympathetic and parasympathetic nerve fibers and respond independently from each other upon nerve stimulation."\n\nfor more info see the website listed in as my source...the contents I quoted were taken directly from there.
971960
Yeah, more mitochondria for energy and more ribosomes (rough ER) to produce proteins necessary for contraction (actin + myosin).\n\nRegards,\nRyan
372330
For most muscles, contraction occurs as a result of conscious effort originating in the brain. The brain sends signals, in the form of action potentials, through the nervous system to the motor neuron that innervates the muscle fiber. However, some muscles (such as the heart) do not contract as a result of conscious effort. These are said to be autonomic. Also, it is not always necessary for the signals to originate from the brain. Some reflexes are fast, unconscious muscular reactions that occur due to unexpected physical stimuli. Other actions such as locomotion, breathing, chewing have a reflex aspect to them; the brain will start the contractions, but continuation of the movements can become reflexive. The action potentials for reflexes to unexpected stimuli originate in the spinal cord instead of the brain.\nThere are three general types of muscle contractions: skeletal muscle contractions, heart muscle contractions, and smooth muscle contractions.\nFor skeletal muscles, the force exerted by the muscle is controlled by varying the frequency at which action potentials are sent to muscle fibers. Action potentials do not arrive at muscles synchronously, and during a contraction some fraction of the fibers in the muscle will be firing at any given time. Typically when a human is exerting a muscle as hard as they are consciously able, roughly one-third of the fibers in that muscle will be firing at once, but various physiological and psychological factors (including Golgi tendon organs and Renshaw cells) can affect that.\nYou can read more here\nhttp://en.wikipedia.org/wiki/Muscle_contraction
154428
I'm not sure if this is enough info but...\nWhen the Left Atrium is full of blood, the heart muscle in the Left Ventricle relaxes so the muscles attached to the Mitral Valve open.
105640
The heart cells are called myocytes that can contract.  Proteins inside the myocyte, actin and myosin, make this contraction possible.  Calcium ions are released very quickly (from the sarcoplasmic reticulum) and trigger the contraction. Then the heart relaxes and gets ready for the next beat.  The contraction is controlled from the top of the heart (the atria) and spreads down to the botton (the ventricles), like a water ripple through a pond but in this case it is through all the cells of the heart.  The coordinated contraction then results in blood being pumped into the lungs and forward through the body.\n\nIf you need a more detalied description let me know.  This is the basic idea though.  The billions of cells of the heart are coordinated to result in proper heart beats.
9977
Weak heart muscle.\nThis causes your heart muscle to either become enlarged and weakened or thickened and stiff. It may result from infection, alcohol or drug abuse, or unknown causes.
697126
Muscle fatiguing and cramping are somewhat related.  \n\nFatigue is do to your muscles using up the ATP in the muscle cell.  The phosphate is essentially exploded off of the ATP, becoming ADP and needs to be replaced.  When it isn't replaced fast enough (which is why body builders take creatine phosphate) some of your muscle filaments aren't able to contract since some of the filaments don't have an expendible phosphate on the ADP.\n\nCramps.  That's a bit vague.  Do you mean soreness after exercise?  Or do you mean when the muscle stays in contraction without effort?\n\nIf you mean soreness, then that is because every time you contract a muscle, it thickens and stretches the epimyceum, the layer of connective tissue that surrounds the muscle.  This is the only part of the muscle that has pain fibers.  he more you contract it, either by intensity or prolonged use, it tears the epimyceum.\n\nUninitiated contraction is due to an electrolyte imbalance.  Either your intake of electrolytes is low, you flushed them out by drinking too much water, or there is excessive lactic acid causing an change in the membrane potential.
100708
the heart is a muscle, it doesn't have muscles in it
282411
It's all to do with the action potential of the muscle cell. We have different sorts of them in our body...eg cardiac, smooth muscle..etc.
527047
Cardiovascular, Muscular Endurance, Muscular strength, flexibility, and Body Composition.
294509
The entire LV wall function is not contracting / relaxing fully to its limit.\n\nWALL MOTION ABNORMALITIES\nNormally the contraction of the heart has a wringing motion, due to the arrangement of cardiac muscle fibers. For global evaluation, 2-D each is a useful tool. The SAX planes show all of the walls, except the apex. The best blood supply is at the base of the heart. \n\n\nHYPERDYNAMIC \ncompensatory decrease in systolic wall thickening \n\n\nHYPOKINETIC \nslow moving wall shows decrease in fractional shortening \n\n\nAKINETIC \nwall may thin in systole \n\n\nPARADOXIC \nwall motion is compensatory and moves opposite of normal \n\n\nDYSKINETIC \nwall motion compensates for abnormal adjacent walls
168110
Effects of exercise on skeletal muscles.\n\nMuscles undergo changes related to the amount of work they normally do.\nProlonged inactivity causes disuse atrophy. \nRegular exercise increases muscle size, called hypertrophy.\nStrength training is exercise-involving contraction of muscles against heavy resistance.\nStrength training increases the numbers of myofilaments in each muscle fiber, and as a result, the total mass of the muscle increases. \nStrength training does not increase the number of muscle fibers.\nEndurance training is exercise that increases a muscle’s ability to sustain moderate exercise over a long period; which is sometimes called "aerobic training."\nEndurance training allows more efficient delivery of oxygen and nutrients to a muscle via increased blood flow. \nEndurance training does not usually result in muscle hypertrophy.\n\nBy\nSURESH KUMAR .M.P.T.,M.I.S.C.P.\nCHARTERED PHYSIOTHERAPIST\nskmpt2002@yahoo.co.uk
923862
are you trying to get us to do your homework!!?\n\nwell i will help you lol!\nmuscles always work in pairs because they can only contract and not ..... ? these pairs are known as antagonistic muscles. For the movement to occur, one muscle shortens (contracts) while the other muscle lengthens (relaxes) the muscle that contracts is known as the.....muscle. Muscles which hold the bone in place are known as tendon muscles\n\nsorry I didn't get them all, those were the ones I could do off the top of my head!
260629
The heart muscle, like every other organ or tissue in your body, needs oxygen-rich blood to survive. Blood is supplied to the heart by its own vascular system, called coronary circulation. \n\nThe aorta (the main blood supplier to the body) branches off into two main coronary blood vessels (also called arteries). These coronary arteries branch off into smaller arteries, which supply oxygen-rich blood to the entire heart muscle.\n\nThe right coronary artery supplies blood mainly to the right side of the heart. The right side of the heart is smaller because it pumps blood only to the lungs.\n\nThe left coronary artery, which branches into the left anterior descending artery and the circumflex artery, supplies blood to the left side of the heart. The left side of the heart is larger and more muscular because it pumps blood to the rest of the body.
1062790
Muscle contraction.  Much like when you stretch, then pull all your muscles together.
434302
diff muscle types have diff shapes and characteristics\n1. Cardiac muscle - spindle shape, nuclei are centrally located, involuntary muscle, branching, primarily found in the heart\n\n2. Smooth muscle - spindle shape, involuntary, not branching, primarily found in the gastrointestinal tract\n\n3. Skeletal muscle - branching, voluntary, multi-nucleited, straited, found all over the body