Motor Units Flashcards
What is a motor unit?
A motor unit is a motor neurone plus all the muscle fibres it initiates.
What is a neurone?
A neurone is a type of nerve cell.
What is the function of an axon?
An axon carries the action potential (AP) from the cell body to the neuromuscular junction.
What is the neuromuscular junction?
The neuromuscular junction is where the motor neurone communicates with the muscle fibres across the synapse.
What is a synapse?
A synapse is the space between the neuromuscular junction and the skeletal muscle.
What is the motor end plate?
The motor end plate is the area of muscle fibre which establishes synaptic contact with the motor neurone.
What is resting potential?
Resting potential is where there is a lower charge inside the neurone than outside the neurone.
What is action potential?
Action potential is the electrical impulse carried down the axon.
What is a neurotransmitter?
Neurotransmitters are chemical transmitters which diffuse across a synapse binding to receptors to initiate muscular contraction.
What is acetylcholine?
Acetylcholine is the neurotransmitter released at the neuromuscular junction and diffuses across the synapse.
What is the all or nothing law?
The all or nothing law states that if the action potential threshold is reached, all the muscle fibres in a motor unit are initiated. If the action potential threshold is not reached, then none of the muscle fibres are initiated.
What is Myoglobin?
A protein that transports oxygen
What is Phosphocreatine?
A high energy compound stored in muscle cells as used as fuels for high intensity energy production
