C3- Action Potential

An action potential occurs regardless of the amount of stimulation received by the cell.

During an action potential, the membrane potential can remain at a negative value regardless of stimulation.

The amplitude of an action potential is lower than that of graded potentials.

The time course of an action potential is directly influenced by the duration of the stimulus.

Action potentials exhibit decremental conduction, meaning they diminish in strength over distance.

The absolute and relative refractoriness characteristics of an action potential allow the cell to respond to new stimuli immediately after firing.

Hyperpolarization can occur during the process of an action potential.

The resting membrane potential is considered an electrical signal.

A threshold value of membrane potential is necessary to trigger the occurrence of an action potential.

Depolarization occurs when the membrane potential goes from -70mV to -40mV.

Hyperpolarization refers to the membrane potential becoming more positive than the outside environment.

Repolarization is the process of returning the membrane potential to its resting state after depolarization.

The inside of a cell becomes positively charged compared to the outside during reverse polarization.

Active responses of the membrane are organized by the muscle cells themselves without any neural translation.

Electrodes are used to measure changes in potential across the membrane during fluctuations.

A big axon is not suitable for exciting and analyzing membrane properties due to its shape.

In an unmyelinated axon, the action potential is regenerated at every patch of membrane, leading to a higher velocity of conduction.

The diameter of an axon does not affect the velocity of conduction of the action potential.

Saltatory conduction occurs in myelinated axons, where action potentials are generated only at the nodes of Ranvier.

In conditions like multiple sclerosis, corrupted myelination prevents action potentials from reaching the effector.

A myelinated axon always conducts action potentials faster than an unmyelinated axon regardless of axon size.

The axon hillock is referred to as the trigger zone where action potentials originate.

An action potential is a digital signal and can be generated anywhere along the neuron's dendrites.

The size of axons has no influence on the ability to conduct an action potential.

The action potential of skeletal muscle fibre lasts longer than that of motor neurons.

Dissipation of graded potentials occurs mainly due to the current lost through the axoplasm.

In a parallel RC circuit model, the capacitor represents the membrane lipids.

Action potentials are continuously regenerated due to the voltage gated sodium channels located near the stimulating site.

As a capacitor becomes charged, its resistance decreases over time.

Graded potentials can be observed far from their stimulating site due to their strong dissipation characteristics.

Myelinated axons exhibit decremental conduction of action potentials due to the presence of channels in the myelin sheath.

When current is injected, there is initially no change in membrane potential because the ion channels are open.

The flow of ions after they enter the intracellular fluid (ICF) is towards the more positive regions.

If axoplasmic resistance is high compared to membrane resistance, it would be easier for current to move along the axon.

The electrical field outside the cell changes as the membrane potential alters, influencing resting potential.

Current always flows through both arms of the circuit simultaneously when the circuit is closed.

The voltage gated Na channels contain only an activation gate.

Na channels are responsible for repolarization and hyperpolarization during the action potential.

Na conductance increases sharply when the threshold value is reached.

The time course of K channel conductance is faster than that of Na channel conductance.

During the action potential, the membrane potential can reach +70mV.

Afterhyperpolarization occurs as K channels return to 0 conductance.

Both Na and K ions can reach their equilibrium potential during an action potential.

A positive feedback loop occurs during the opening of Na channels in response to depolarization.

The activation gate of voltage gated Na channels is open when the cell is at rest.

The inactivation gate opens immediately after the cell reaches the threshold potential.

Both the activation gate and the inactivation gate can be open at the same time.

Once the inactivation gate starts closing, the cell can immediately elicit another action potential.

An action potential can be elicited when the inactivation gate is open and the activation gate is closed.

The sodium channel transitions from a closed to an open conformation solely based on internal cellular conditions.

As membrane potential reaches +30 mV, the inactivation gate begins to close.

The cycle of sodium channel activation directly determines the time course of action potentials, making them variable.

When the membrane potential goes from -50 mV to -49 mV, sodium channels begin to close.

Hyperpolarization results from an increase in the membrane potential above the threshold.

During action potential, there is a window when the sodium can enter the cell due to both gates being open.

During absolute refractoriness, a new action potential can be elicited regardless of the intensity of the current.

Relative refractoriness allows a new action potential to be triggered, but requires an increased stimulus strength compared to a typical situation.

Changes in the interstitial fluid's potassium concentration have no impact on the membrane potential.

Action potentials in different excitable cells, such as myocardial muscle cells and motor neurons, exhibit identical time scales and courses.

During the process of generating an action potential, hyperpolarization makes it easier for the cell to trigger another action potential.

If an excitable cell reaches the threshold spontaneously, it will not elicit an action potential.

The ability of the action potential to communicate effectively is dependent on its precise sequence of events.

An action potential can occur randomly, resulting in random excitations of cells.

Both sodium and potassium conductance are key factors influencing the property of refractoriness in excitable tissues.

The Nernst equation is irrelevant when discussing changes in membrane potential.