It's during the "rising phase" when the membrane potential becomes more positive.
Increasing extracellular potassium concentration can depolarize the cell membrane potential because potassium ions are leaking out of the cell less efficiently, leading to an accumulation of positive charge outside the cell. This disrupts the normal balance of ions and can make it easier for the cell to depolarize and generate an action potential.
Cells with unstable resting membrane potentials, such as pacemaker cells in the heart or neurons in the brain, can continually depolarize due to the presence of a "funny" current (If) that slowly depolarizes the cell until it reaches the threshold for an action potential to be generated.
Valium (diazepam) acts as a positive allosteric modulator of GABA-A receptors, leading to an increase in inhibitory synaptic transmission. This typically causes hyperpolarization of the cell membrane potential, decreasing the likelihood of action potential firing.
This likely refers to the process of creating an action potential in a neuron. Negative ions, such as chloride or potassium, flow into the neuron to depolarize the cell membrane, making it more positive inside. This initiates the electrical signal that travels along the neuron.
No, action potential involves the influx of positive ions, specifically sodium ions, to depolarize the membrane. This influx of positive ions leads to the change in membrane potential, allowing for the message to be transmitted along the neuron.
Increasing extracellular potassium concentration can depolarize the cell membrane potential because potassium ions are leaking out of the cell less efficiently, leading to an accumulation of positive charge outside the cell. This disrupts the normal balance of ions and can make it easier for the cell to depolarize and generate an action potential.
Cells with unstable resting membrane potentials, such as pacemaker cells in the heart or neurons in the brain, can continually depolarize due to the presence of a "funny" current (If) that slowly depolarizes the cell until it reaches the threshold for an action potential to be generated.
Valium (diazepam) acts as a positive allosteric modulator of GABA-A receptors, leading to an increase in inhibitory synaptic transmission. This typically causes hyperpolarization of the cell membrane potential, decreasing the likelihood of action potential firing.
This likely refers to the process of creating an action potential in a neuron. Negative ions, such as chloride or potassium, flow into the neuron to depolarize the cell membrane, making it more positive inside. This initiates the electrical signal that travels along the neuron.
Increasing the extracellular potassium concentration can depolarize the resting membrane potential, making it less negative. This can lead to increased excitability of the cell.
No, action potential involves the influx of positive ions, specifically sodium ions, to depolarize the membrane. This influx of positive ions leads to the change in membrane potential, allowing for the message to be transmitted along the neuron.
Depolarization refers to the change in electrical charge across a cell membrane, where the inside becomes less negative. Repolarization is the return to the cell's resting membrane potential after depolarization. These processes are essential for transmitting electrical impulses in nerve and muscle cells.
Calcium depolarizes cell membranes.
If the permeability of a resting axon to sodium ion increases, more sodium ions will flow into the cell, leading to depolarization and the generation of an action potential. If the permeability decreases, fewer sodium ions will enter, making it harder to depolarize the cell and initiate an action potential.
If a resting neuron is stimulated and there is an inward flow of positive charges into the cell, the membrane potential will depolarize, meaning the inside of the cell becomes less negative. This can trigger an action potential if the depolarization reaches the threshold level.
Endocytosis is the process where a molecule causes the cell membrane to bulge inward, forming a vesicle to bring the molecule inside the cell. This is distinct from exocytosis, which is the process of releasing molecules from a cell by fusing vesicles with the cell membrane and expelling their contents.
Acetylcholine (ACh)