sw33t_lil_azn08 asked:

Each muscle cell is a
a.fasciculus.c.fiber.
b.sarcomere.d.myofibril.

____41.Before being released from the axon of a neuron, acetylcholine is stored in the
a.synaptic vesicles.c.muscle fiber.
b.synaptic cleft.d.postsynaptic membrane.

____42.During the process of muscle contraction, calcium ions bind to the
a.presynaptic terminal.c.synaptic vesicles.
b.sarcolemma.d.troponin molecules.

____43.During muscle contraction, which of these processes requires ATP?
a.calcium ions are moved back to the sarcoplasmic reticulum
b.cross-bridges are released
c.heads of the myosin myofilaments are bent toward the center of the sarcomere
d.all of these

____44.Even though each muscle fiber responds in all-or-none fashion, a whole muscle can contract with varying force because of
a.different threshold values.c.recruitment of additional motor units.
b.total tetanus of the muscle.d.rigor mortis.