8.1 The Control of Movement Flashcards
Smooth muscles
Those that control the digestive system and other organs
Cardiac muscles
Muscles of the heart that have properties intermediate between those of smooth and skeletal muscles
Skeletal (striated) muscles
Muscles that control movement of the body in relation to the enviroment
Neuromuscular junction
A synapse between a motor neuron axon and a muscle fiber
Antagonistic muscles
Opposing sets of muscles that are required to move a leg or arm back and forth
Flexor
Muscle that flexes the limb
Slow-twitch fibers
Muscle fibers that have less vigorous contractions and no fatigue
Extensor
Muscle that straightens the limb
Stretch reflex
A reflexive contraction of a muscle in response to a stretch of that muscle
Fast-twitch fibers
Muscle fibers that produce fast contractions but fatigue rapidly
Proprioceptor
A receptor that detects the position or movement of a part of the body
Reflexes
Automatic muscular responses to stimuli
Muscle spindle
A receptor parallel to the muscle that responds to a stretch
Aerobic
Requiring the use of oxygen during movements
Rooting reflex
When an infant turns toward the stimulated cheek and begins to suck
Golgi tendon organs
Receptors that respond to increases in muscle tention; inhibit futher contractions
Anaerobic
Proceeding without using oxygen at the time of a reaction
Grasp reflex
A reflexive grasp of an object placed firmly in the hand
Motor program
A fixed sequence of movements
Babinski reflex
The extention of the big toe and fanning of the others, by an infant, when the sole of the foot is stroked
Ballistic movement
Motion that proceeds as a single organized unit that cannot be redirected once it begins
Central pattern generators
Neural mechanisms in the spinal cord that generate rhythmic patterns of motor output
