MEDICAL PHYSIOLOGY

Detailed explanation-1: -This means that some event (a stimulus) causes the resting potential to move toward 0 mV. When the depolarization reaches about-55 mV a neuron will fire an action potential. This is the threshold. If the neuron does not reach this critical threshold level, then no action potential will fire.

Detailed explanation-2: -Threshold of excitation(threshold): The level that a depolarization must reach for an action potential to occur. In most neurons the threshold is around-55mV to-65mV.

Detailed explanation-3: -The minimum stimulus needed to achieve an action potential is called the threshold stimulus. The threshold stimulus causes the membrane potential to become less negative (because a stimulus, no matter how small, causes a few sodium channels to open and allows some positively-charged sodium ions to diffuse in).

Detailed explanation-4: -Answer and Explanation: Generally, a threshold stimulus is the smallest amount of stimulation or force that is needed to initiate a response. A physiological example can be observed when considering cell excitability to produce a muscle twitch.

Detailed explanation-5: -When a neuron is sufficiently stimulated to reach the neural threshold (a level of stimulation below which the cell does not fire), depolarization, or a change in cell potential, occurs. Potentials. The term potential refers to a difference in electrical charges.