Chap 9 Muscular System Flashcards
Acetylcholine
Neurotransmitter that is secreted from the nerve terminals of cholinergic fibers; found in the CNS, neuromuscular junctions, and synapses of the parasympathetic nerves
Actin
One of the contractile proteins in muscle; forms the thin filament
Antagonist
A muscle that exerts an opposing effect
Aponeurosis
Broad, flat sheet of fibrous connective tissue that connects muscle to another structure
Cardiac muscle
Type of striated muscle found in the heart; the myocardium
Contraction
Shortening of a muscle so as to cause movement or tension development
Cross- bridges
Temporary binding of myosin heads and actin causing muscle contraction and tension development
Fascia
Fibrous connective tissue membrane that covers individual skeletal muscles or certain organs
Insertion
The more movable attachment point of a muscle to a bone
Motor unit
Refers to the somatic motor neurons that carries information away from the central nervous system
Muscle fiber(cell)
Muscle cell composed of a series arrangement of sarcomeres
Myosin
Muscle protein that interacts with actin yo cause muscle contraction; also called the thick filament
Neuromuscular junction
Junction or space that occurs between a motor neuron and a muscle fiber
Origin
The part of the muscle attached to the more immovable structure
Prime mover
The muscle that is most responsible for a particular movement
Recruitment
Enlistment of additional motor units to increase the force of muscle contraction
Relaxation
The state of being free of tension, as in the uncontracted muscle state
Sacomere
Contractile unit of a muscle extending from Z line to Z line; contains the contractile proteins and the thick and thin filaments
Sarcoplasmic reticulum
Calcium storing endoplasmic reticulum located in muscle
Skeletal muscle
Striated voluntary muscle that lies over parts of the skeleton; causes movement of the skeleton
Sliding filament mechanism
The mechanism of muscle contraction whereby the sarcomeres shorten in response to the interaction between the contractile proteins; actin and myosin
