Skeletal Muscular Contraction Flashcards
What sends the electrical impulse during a muscle contraction?
CNS
Give an example of an isometric contraction?
The plank
What is an isometric contraction?
A contraction with no change in muscle length
What is an isotonic eccentric contraction?
Lengthening of muscle in a contraction
What is an isotonic concentric contraction?
Shortening of a muscle during a contraction
What are motor neurons?
Specialised cells that transmit nervous impulses from the CNS to muscle fibres
What two things must happen for a muscle contraction?
- There must be enough action potential
- Acetylcholine must be present in the synaptic cleft
What flows through the synapse?
Acetylcholine, a neurotransmitter
What is the ‘All or None Law’?
If action potential isn’t above threshold, no muscle fibres will contract
What is an isotonic contraction?
A change in muscle length to support a movement
What happens when action potential reaches the neuromuscular junction?
The impulse needs to cross the synaptic cleft
In skeletal muscular contraction, what is the electrical impulse known as?
The action potential
What is the role of the cell body in skeletal muscular contraction?
The cell body sends the electrical impulse to the motor-end plate
What is the role of the axon in skeletal muscular contraction?
The axon branches off the cell body and sends the action potential to the motor-end plate
