Question

The "all-or-nothing event" refers to the fact that

a. Cells are continuously active.
b. Action potentials occur completely or not at all.
c. Electrical current crosses the synapse completely or not at all.
d. The neurons in a particular "lobe" of the brain fire or none of them fire.

Answer 1

An action potential is an all-or-nothing event that occurs completely or not at all. It allows for rapid communication within the nervous system. Injury perception is equally painful regardless of body location.

Step-by-step explanation:

An action potential is an all-or-nothing event, meaning that it either occurs completely or not at all. When an action potential is generated, it is propagated at full strength along the axon of a neuron. This property allows for rapid and efficient communication within the nervous system. For example, if you stub your toe, the action potential generated by the sensory neurons in your toe is perceived by your brain as equally painful as an injury to your nose.

Answer 2

An action potential is an all-or-nothing event that b). Action potentials occur completely or not at all.

Step-by-step explanation:

An action potential is an all-or-nothing event, meaning that it occurs completely or not at all. It is a momentary change in the electrical potential of a neuron membrane that travels along the axon. This property allows for the rapid and reliable transmission of signals in the nervous system.

When an incoming signal from another neuron is strong enough to reach the threshold of excitation, an action potential is generated. It then travels down the axon at full strength, without fading away. This phenomenon is similar to a lit fuse of a firecracker; it either ignites fully or does not ignite at all.

The all-or-nothing nature of action potentials explains why our brain perceives pain equally from distant body parts. For example, an injury to the toe and an injury to the nose can elicit the same level of pain because action potentials are propagated at their full strength regardless of the distance from the injury. The correct answer is b). Action potentials occur completely or not at all.