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What are the two types of graded potentials?

Graded potentials can be of two sorts, either they are depolarizing or hyperpolarizing (Figure 1).

Are graded potentials always excitatory?

Yes. The ‘average’ neuron has 1000 neurons that synapse on it and tell it what to do by creating graded potentials. Some are excitatory ( depolarizing) and some are inhibitory (hyperpolarizing).

What is a graded response?

a response that increases with the amount of energy supplied as opposed to the reaction brought about by the ALL-OR-NONE LAW.

Are EPSP and IPSP graded potentials?

A depolarising graded potential is known as an excitatory postsynaptic potential (EPSP). A hyperpolarising graded potential is known as an inhibitory postsynaptic potential (IPSP).

When two or more graded potentials arrive at the trigger zone?

When two or more graded potentials arrive at the trigger zone, which of the following could happen? An excitatory and inhibitory signal can cancel each other out; two excitatory stimuli may be additive, and summation could occur; and two inhibitory stimuli may be additive, resulting in lower excitability.

Why are action potentials Nondecremental?

The nondecremental characteristic of the action potential means that once a neuron begins conducting, the impulse is propagated to the very end of the axon without diminishing. Potentials in the dendrites are also decremental; they fade as they are propagated toward the cell body.

Do action potentials get weaker with distance?

The action potential travels down the axon as the membrane of the axon depolarizes and repolarizes. An electrical potential that is initiated by stimulation at a specific site, which is a graded response that spreads passively across the cell membrane, decreasing in strength with time and distance.

Are action potentials all-or-none?

Action potentials work on an all-or-none basis. This means that an action potential is either triggered, or it isn’t – like flipping a switch. A neuron will always send the same size action potential.

What is the relation between action potentials and stimulus intensity?

Third, nerve cells code the intensity of information by the frequency of action potentials. When the intensity of the stimulus is increased, the size of the action potential does not become larger. Rather, the frequency or the number of action potentials increases.

How do neurons code for stimulus intensity?

Stimulus intensity is encoded in two ways: 1) frequency coding, where the firing rate of sensory neurons increases with increased intensity and 2) population coding, where the number of primary afferents responding increases (also called RECRUITMENT).

What is stimulus strength?

the actual intensity of a stimulus or its ability to elicit a desired response.