Question | Answer |
Contractility | ability of skeletal muscle to shorten with force |
Excitability | capacity of skeletal muscle to respond to a stimulus |
Extensibility | ability to be stretched |
Elasticity | ability to recoil to their original resting length after they have been stretched |
Three types of muscle | skeletal, smooth, cardiac |
connective tissue sheath that Surrounds each skeletal muscle | epimysium |
loose connective tissue located outside the epimysium; surrounds and separates muscles | Fascia |
visible bundles that make up muscles | fasciculi |
loose connective tissue that surrounds the fasciculi | perimysium |
single muscle cells that make up fasciculi | |
each fiber is surrounded by a connective tissue sheath called | endomysium |
cytoplasm of each fiber is filled with___, a threadlike structure that extends from one end of the fiber to the other | myofibrils |
Myofibrils contain these 2 major types of protein fibers(myofilaments) | actin(thin) and myosin(thick) |
Actin and Myosin myofilaments form highly ordered units called | sarcomeres |
basic structural and functional unity of the muscle | sarcomeres |
the charge difference across the membrane | resting membrane potential |
the brief reversal back of the charge is called | action potential |
nerve cells that carry action potentials to skeletal muscle fibers | motor neurons |
Axons enter | muscles and branch |
Each branch that connects to the muscle forms a ___ or ___ near the center of the cell | neuromuscular junction or synapse |
A single motor neuron and all the skeletal muscle fibers it innervates are called | a motor unit |
the enlarged nerve terminal is the | presynaptic terminal |
the space between the presynaptic terminal and the muscle cell is the | synaptic cleft |
the muscle fiber (in nerves) | postsynaptic terminal |
each synaptic terminal contains | synaptic vesicles |
synaptic vesicles secrete a neurotransmitter called | acetylcholine |