BY 124 L Muscle Physiology Handout

BY 124 L Muscle Physiology Handout What are the three basic muscle types? ️️cardiac, smooth, skeletal skeletal muscle is usually attached to what? ️️bone what do skeletal muscles move? ️️skeleton the ___ nervous system controls skeletal muscles ️️somatic are skeletal muscles voluntary or involuntary ️️voluntary where do you usually find smooth muscle? ️️hollow organs and tubes-stomach, intestines, bladder, blood vessels smooth muscle is controlled by the _____ nervous system ️️autonomic smooth muscle control is largely what ️️involuntary where is cardiac muscle found? ️️heart what two factors does it respond to? ️️ANS and hormones skeletal muscle contains many muscle cells called ___ which are bound by what? ️️muscle fibers connective tissue a single muscle cell contains many ___ which extend the length of the cell ️️myofibrils muscle cells contract along their ___ ️️length striations are seen in which two types of muscle ️️cardiac and skeletal myofibrils contract ___ which in turn contract ____ ️️muscle fibers muscles myofibrils exhibit alternate dark and light bands alone their what? this results in a similar banding pattern seen in the muscle cell itself ️️length skeletal muscle is often called what ️️striated muscle which 2 of 3 muscle are striated? ️️cardiac and skeletal in a myofibril, the dark bands are called ️️a bands in a myofibril the light bands are called ️️I bands in the middle of the I bands are other bands called ️️Z lines The A bands have light areas bisected by bands called ️️M lines the functional unit of the myofibril is called a ️️sarcomere a sarcomere extends from what to what ️️one z line to another contraction of myofibrils is caused by the contraction of each ️️sarcomere a sarcomere is comprised of two proteins called what ️️actin and myosin a thin filament consists mostly of 2 molecules of ️️actin a thick filament is comprised of hundreds of ____ molecules ️️myosin thin filaments are connected to the ____ a structure that runs across the myofibril ️️z line the thick filaments are connected to the ____, a structure that runs across the myofibrils ️️m line the dark areas of the A band correspond to the regions where what two structures overlap ️️thick and thin overlap the light area in the middle of the A band (called the ___) consists of thick filaments only ️️H zone the width of the A band corresponds to what? ️️length of thick filaments the ______ corresponds to regions consisting of thin filaments only ️️I bands both types of filaments are anchored, thin to ___ and thick to _____ ️️Z line M line the Z and M lines run through the myofibrils and thus align what? ️️sarcomere the width of the ___ band remain constant throughout contraction ️️A contraction does narrow the __ bands and the __ zone as the __ lines come closer together. also the dark areas of the __ band becomes wider ️️I