Cardiac muscle introduction

What are desmosomes for?strong physical linkage for cardiac cellsdesmosomes and jap junctionshow would you describe the mitochondria in cardiac muscle cells?numerous and large (huge ATP production)what triggers the release of cardiac muscles?extracellular Ca++explain gap junctionsion flow directly from cell to cell electrically linking them (cells have the same electricity and do the same regulated coordinated contraction)What can't a cardiac muscle be pulled?cells have very strong physical attachment (though desmosomes)What are gap junctions disrupted by?changes in pHmust be what where in order to have extracellular Ca++ trigger the releasevoltage gated channels of Ca in t tubulesThe Ca++ makes a different ______ in cardiac muscleAPskeletal muscle ap vs. cardiac muscle apcompared to skeletal muscle, cardiac muscle has a _______ absolute refractory period which keeps _______ separatelong contractionswhy does cardiac muscle need a long absolute refractory period?relaxation time for blood to flow into heartwhat forces the heart to have a period of relaxation in order to fill the heart?absolute refractory periodautorhythmic can be interchangeable withpacemakerspacemakers =some self-depolarizewhat does self depolarize mean?sets the basic beat of the heartFor signal transmission, some function like ____autorhythmic cells signal transmissionauto rhythmic cells are Long, keeps contractions _____describe the base rhythm for cardiac tissuestimulus starts in pacemaker and travels to contractile cells in one locationhow does cardiac tissue contract and why?in waves due to gap junctionsWhat are the cells linked to in cardiac tissuefibrous CTwhat is referred to as the "skeleton of the heart?"fibrous CT that is linked to cardiac tissuewhat are the two things that can affect the basic rhythm of the heart?Rate (speed) and forcethe rate and force of cardiac tissue is affected by ______autonomic NSwhat effect does the sympathetic nervous system have on the rate and force of cardiac tissue and how?increases both by an increase in Na+ influx via leak channel of autorhythmic cells, also due to norepinephrinewhat effect does the parasympathetic nervous system have or the rate and force of cardiac tissue and how?decreases both by a decrease of Na+ influx via leak channel of autorythmic cells, also due to Achwhat neurotransmitter is commonly associated with the sympathetic nervous system?Achwhat neurotransmitter is commonly associated with the parasympathetic nervous system?NorepinephrineWhich effect (either sympathetic or parasympathetic) dominates the heart at rest?parasympatheticwhat is it called when the parasympathetic NS takes control of the heart rate?vagal toneCompare and contrast Cardiac and smooth muscleCardiac Both Smooth Striated not striated heart internal organs short filaments long filaments more SR less SR Involuntary no troponin Ca++ signalCompare and contrast cardiac and skeletal musclesCardiac both Skeletal striated involuntary voluntary cardiac most of body cells called fiberswhich of the following is true regarding the absolute refractory periods of cardiac muscle cells?it is longer that in skeletal muscle and keeps contraction separatewhat is the source of calcium for triggering contraction in cardiac muscle?sarcoplasmic reticulum and Ca++ influxHow are cardiac muscle cells connected?gap junctions and desmosomeswhich neuronal input dominates at rest?parasympathetic via vagus nervewhat is the greatest supplier of ATP?aerobic respiration