the muscular system: contraction and relaxation Flashcards
how does contraction work
communication between the muscle tissue, the nervous system and the blood vessels
what are nervous system cells
motor neurons
attached to muscle fibers
what is the blood used for
brings energy-supplying nutrients
takes away waste products
what are the 4 main steps of contraction
- communication between a motor neuron and the skeletal muscle at the neuromuscular junction
- excitation of the muscle fibers
- excitation-contraction coupling
- cross-bridge cycling
what is a neuromuscular junction
he location where a motor neuron touches a muscle fiber
what is a synaptic cleft
the gap between the motor neuron and the sarcolemma
a motor neuron secretes a chemical what is it called
neurotransmitter also called acetylcholine
what is a neurotransmitter used for
to cross the synaptic cleft
what is muscle fiber excitation
the end plate potential causes an electrical current to be generated which propagates like a wave across the sarcolemma
what is an action potential
it’s the electrical current
what is excitation-contracting coupling
myosin must bind with actin in order for contraction to occur
what blocks myosin
tropomyosin
what is cross-bridge cycling
the part where the muscle actually contracts
3 main places where muscle contraction is turned off
the neuromuscular junction
the sarcoplasmic junction
cross-bridge cycling
what is the first 6 seconds of work called
instantaneous work
ATP is present in the sarcoplasm
