HISTOLOGY
NERVOUS TISSUE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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time between binding of the neurotransmitter and firing of an action potential
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minimum stimulus necessary to initiate an action potential
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total amount of neurotransmitter it takes to cause an action potential
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voltage across the resting cell membrane
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Detailed explanation-1: -The minimum stimulus required to trigger an action potential is known as the threshold stimulus. In order for an action potential to be produced, a stimulus (or combination of stimuli) must depolarize to the membrane from-70 mV to the threshold potential of-55 mV.
Detailed explanation-2: -PROPAGATION OF THE NERVE IMPULSE The threshold potential for most excitable cells is about 15 mV less negative than the resting membrane potential. In a nerve, if the membrane potential decreases from-70 mV to-55 mV the cell fires an action potential which propagates along the axon.
Detailed explanation-3: -Threshold is the minimum current required for the cell membrane to generate an action potential. True. For an action potential to happen, a local potential must rise to a critical voltage called the threshold (typically about-55 mV)-the minimum needed to open voltage-gated channels.