In: Anatomy and Physiology
An increase in action potential frequency of a motor neuron would result in which of the following (select all that apply):
A) Increased Ca2+ in the sarcoplasm.
B) Increased influx of Ca2+ ions.
C) Increased muscle fiber contraction.
D) Decreased activity of AChE.
E) Decreased release of ACh.
Anawer
motor neuron giving impulse to various tissues like muscle , glands , .
they relay effector responce innresponce to affector stimuli
moto neuron send impulse to the muscle through action of neurotransmitters. which are tranmitted from presynaptic neurons into neuro muscular junctions. for the relaese of neurotransmitters from presynaptic neurons needs the entry of calcium through voltage gated channel.
the neurotransmitters like acetyl choline then released into the neuromuscular junction. which binds with post synaptic membrane or muscle membrane and cacuse entry of sodium through voltage gated channel and induces action potential in the muscles.(the excess acetylcholine in the neuromuscular junction are degraded with the enzyme acetylcholine esterase). this causes opening of ryanodine receptors in the sarcoplasmic reticulam inside muscle fibres and cause releases of more calcium into the sarcoplasm . this calcium helps in muscle contraction by bind with troponin and exposes active site on actin. ATP then binds to myosin , moving the myosin to its high energy state , releases myosin head frommactin active site
so in the given options , the increased action potential of a motor neurons results in
increased calcium in sarcoplasm
increased influx of calcium ions
increased muscle contraction
decreased activity of acetylcholine esterase