Somatic Nervous System
That division of the nervous system which innervates skeletal muscle.
All of the muscle fibers innervated by a single motor neuron.
Elongated, cylinder shaped cells that are also called muscle fibers.
The contractile filaments that are arranged in such a way as to produce alternating light and dark bands within the muscle fiber.
Autonomic Nervous System
That division of the nervous system which innervates smooth muscle, heart, and glands.
The unique junctions between cardiac muscle fibers. Provides continuity in transmission of excitation which allows the heart to pump blood into the arteries in a coordinated manner.
The pattern of distribution of nerve fibers in a tissue organ.
A brief, sustained contraction resulting from high frequency stimulation.
A progressive failure of muscle to regain its original length following prolonged stimulation.
Originating within the muscle
A period of time following stimulation when a second stimulus does not produce a result.
Chemicals, released at nerve endings, responsible for producing the effects of nerve stimulation (for example Acetylcholine and Norepinephrine)
The response of a muscle to a single, brief threshold stimulus.
The stimulus strength at which muscle contraction occurs.
Motor Unit Stimulation
Multiple motor units are involved in a contraction, producing a smooth continuous response.
This involves the number of motor units involved in a contraction. More and more motor units are recruited or involved in stronger contractions.
This occurs when stimuli are delivered so frequently that a muscle does not completely relax after first stimulus and second contraction is stronger than first.
A muscle changes in length, but remains constant during the contractile period.
During this type of muscle contraction, the tension increases, but the muscle does not change in length.