Mutation would be the best answer.
Answer:
A- Acetylcholine is released by axon terminals of the motor neuron.
Explanation:
The general mechanism of muscle contraction can be explained as follows:
a) The action potential which is generated, travels along the motor nerve to its ends on muscle fiber (or motor end plate) at the neuro-muscular junction.
b) The nerve endings then secrete small amounts of neurotransmitter called acetylcholine.
c) The actylecholine binds to the receptors on the membrane of muscle fiber and opens the voltage gated sodium channels.
d) Opening of these channels leads to flow of large quantities of sodium ions into the muscle fiber which ultimately results in initiation of action potential in muscle fiber.
e) This action potential depolarizes the fiber including the T-tubules, triggering the release of calcium ions from sarcoplasmic reticulum.
f) The calcium ions thus released initiated the process of muscle contraction.
Rain and snow will occur in low air pressure.
When the pressure of the air is low, the air rise upward in the atmosphere and gets cool and condenses. The condensation causes the formation of clouds from water droplets and snow particle around the dust particle in the sky and at last the the condensation of water vapor causes the formation of rain.
Answer:
Letting go of regrets and past decision.
Explanation: