Anatomy pt. 2

the sarcoplasmic reticulum releases

calcium ions

the phase in which the stimulus frequency so high that the relaxation phase is eliminated

complete tetanus

a layer of collagen fibers that surrounds an entire muscle

epimysium

a muscle _____ contains a sarcolemma, sarcoplasm, myofilaments, and myofibrils

fiber

transmit electrical impulses to the cell's interior

function of the transverse tubule

fast fibers

have high glycogen reserves

skeletal muscle fibers differ from "typical cells" in that these muscle fibers___

have many nuclei

during activities requiring aerobic endurance

most of the muscle's energy is produced in mitochondria

the specialized sarcolemma that contains acetylcholine receptors is the

motor and plate

____ can only contract

muscle cells

a sheath of connective tissue surrounding a bundle of striated muscle fibers is called

perimysium

muscle fascicles are separated by

perimysium

a person whose genetic makeup makes him or her a better marathon runner than a sprinter probably has more ___ in his or her leg muscles

slow fibers

nonstriated, involuntary muscle is

smooth

results from a bacterial toxin that prevents the release of acetylcholine at the axon terminals

botulism

the enzyme acetylcholinesterase causes acetylcholine to

break down

acetylcholinesterase is found within the _____

synaptic cleft

the ____ contains vesicles filled with acetylcholine

synaptic cleft

step that ends contraction

ACh is broken down by AChE

a stimulus for contraction in skeletal muscle

acetylcholine

myofibrils are made of

actin and myosin

the straited appearance of skeletal muscle results from

actin and myosin arrangement

smooth muscle cells

are spindle-shaped

occurs when glycosis produces pyruvate faster than it can be used by the mitochondria

lactic acid is produced