Lecture 5, Nerve/Muscle 1 Flashcards
What is a bundle of axons called?
Fascicle
What are the three types of neuronal communication?
Neuron to neuron, neuron to muscle, and neuron to organs.
How do neurons signal to other neurons and cells?
Bioelectricity and neurotransmitters.
What are parts of the input and output zone called?
Input= Dendrites and cell body (soma): Output= Synaptic terminals
The bioelectricity generated in a neuron passes its bioelectricity onto another neuron, this is what they use to communicate. What is this process called?
Action potential
An action potential is the propagation of a change in voltage, describe depolarisation and repolarisation:
Depolarisation: Cell becomes more positive
Repolarisation: Cell returns to resting voltage (negative).
What are the three main subtypes of muscles?
Cardiac, smooth, skeletal.
What are the 5 layers of muscle?
Whole muscle (bundle of fascicles) → Fascicles (bundles of fibres) → Cells (myofibres) → Myofybrils → Myofilaments (actin and myosin)
What is a sarcolemma?
A cell membrane that surrounds each myofibre.
What is a sarcomere?
A functional unit comprised of thin and thick myofilaments (contractile unit).
What are the extensions of the sarcolemma that dive deep into the muscle? (Regulatory unit)
Transverse tubules (t-tubules)
What two types of myofilaments make up the sarcomere?
Actin (thin filament), myosin (thick filament).
What is a motor unit?
A motor neuron and all of the muscle fibres that it innervate.
Axon to myofibre number of connections.
Only one myofibre is innervated by one axon, however one axon can innervate multiple myofibres.
What is recruitment in relation to motor units?
The number of motor units activated at any time can be varied to change the amount of force produced.
