Compare And Contrast Graded Potentials And Action Potential

Improved Essays
Resting membrane potential is the difference in voltage of the fluids inside a cell and outside a cell and the membrane is said to be polarized. According to the book the value of the resting membrane potential varies from -40 mv to -90 mv in different types of neurons. There are two essential factors that build and generate the resting membrane potential: the differences in the ionic composition of the intracellular and extracellular fluids, and the differential permeability of the plasma membrane. When a cell is at the resting stage, the fluid inside of it is more negative than the fluid outside of it, which usually has a charge of 0 mV. This is because of electrically charged particles called ions. Inside the cell, there is a lower …show more content…
Na+ ions are involved in both of these potentials. Both, graded potentials and action potentials result from a depolarization in the resting potential of a plasma membrane. Graded potentials result from the passive electrical property of the neuron membrane, whereas action potential result from an orchestrated response to depolarizing stimuli and involve an activity of voltage-gated ion channels. A graded potential is a difference in charge across the membrane of a cell. If there are enough positive ions that cross to the inside of the cell, then the charge will become less negative and rises to approximately -50 mv, which results in an action potential. The magnitude of the charge of the membrane potential in graded potentials depends on the strength of the stimulus. Action potentials are long-distance signals of axons only found at the pre-synaptic neuron and graded potentials are short-distance signals of dendrites and cell bodies found at the post-synaptic neuron. Graded potentials are not the nerve signals that travel along an axon, but influence their generation. Graded potential can be either depolarization or hyperpolarization. If threshold is reached, depolarization occurs, voltage-gated ion channels open and an action potential is developed. Actions potentials are an “all or nothing” phenomenon, there is no variance …show more content…
The cerebral cortex has deep grooves called fissures that separate some regions. The longitudinal fissure separates the left cerebral hemisphere from the right cerebral hemisphere. On the other hand, the transverse cerebral fissure separates the cerebral hemispheres from the cerebellum. The cerebral cortex contains three kinds of functional areas: Motor areas, sensory areas, and association areas. The motor areas control voluntary movements. The sensory areas are the regions where we have conscious awareness of sensation and the association areas are the areas that interpret and integrates diverse

Related Documents

  • Improved Essays

    Resting Membrane Potential When a neuron is not transmitting a signal, it is at rest. During resting potential, between the inside and outside of the neuron there is an ion displacement. The inside of the neuron is negative in comparison to the outside. The outside of the cell has a positive charged sodium and negatively charged chlorine, while potassium, positively charged, is more heavily charged inside the cell. This difference in the charge of sodium, chloride, and potassium maintains the dynamic equilibrium in the neuron.…

    • 815 Words
    • 4 Pages
    Improved Essays
  • Decent Essays

    Fluorine has the most ionization energy and Caesium with the least. As you go across a period, energy is increased along the periods. Ionic radius– Ionic radius is the measurement of distance between the nucleus and electron in the outer shell. When an electron is lost from an atom it can form to a cation, the lost electron will no longer be a part of defending the other electrons from the charge of the nucleus. As you go drown a group, the ionic radius gets bigger.…

    • 589 Words
    • 3 Pages
    Decent Essays
  • Superior Essays

    Al, Alloy 1 And Elece

    • 1504 Words
    • 7 Pages

    Fig. 2 indicates that open circuit potential of Alloy 1, 2 (especially Alloy2) is more negative than that of Al. It can be seen that the potential of the Al electrode shifts in the positive direction and achieves a stable value of about -0.82 V. This is due to the formation of natural oxide layer on the Al surface which is stable in saline environments and leads to ennoblement of the…

    • 1504 Words
    • 7 Pages
    Superior Essays
  • Great Essays

    Nernst Equation Lab Report

    • 1740 Words
    • 7 Pages

    Chemical gradient refers to the concentration differences of ions across the membrane while electrical gradient describes the membrane’s selective permeability to specific ions. Together, they combine to create the electrochemical gradient. The difference between the two is known as the cell’s resting membrane potential (Vm) and represents the cell’s potential for doing work. The resting membrane potential includes how the concentration and permeability of all present ions affect the electrochemical gradient of the membrane. These ions include sodium [Na+], chloride [Cl-], and potassium [K+] (Strickholm and Wallen…

    • 1740 Words
    • 7 Pages
    Great Essays
  • Superior Essays

    The entropy of the process was determined from the transition enthalpy and temperature values. Based on the positive enthalpy and entropy values, the reaction appears nonspontaneous. The Gibbs free energy, however, is a better indicator or spontaneity. In order to calculate Gibbs free energy, As the temperature increases the Gibbs free energy decreases. This shows a movement towards disorder with increase of temperature.…

    • 1185 Words
    • 5 Pages
    Superior Essays
  • Improved Essays

    Hooge Essay

    • 726 Words
    • 3 Pages

    For example, the noise in metallic films is a strongly dependent on temperature and the type of substrate, even when the number of charge carriers does not vary much. This observation cannot be explained by using Hooge’s relationship. 1.2.2 The McWhorter Model According to this model, fluctuations in the surface density of electrons, which results into fluctuation in conductivity, arise from exchange of electrons between the surface layer and traps lying in the oxide layer covering the surface. The transfer of electrons took place via tunneling. Since the tunneling probability decreases exponentially with separation between surface and trap, so does the characteristic inverse relaxation time.…

    • 726 Words
    • 3 Pages
    Improved Essays
  • Improved Essays

    This led to an increase in resistivity and a decrease in the conduction. The value of activation energy from table 2 indicates that the conduction process in the present Co-Cr nano ferrite system is due to hopping of polarons. The substitution of Cr ion cobalt ferrites results in the formation of stable electric bonds between the Cr3+ and Fe2+ ions. This localizes Fe2+ charge carriers and hampers the Verwey mechanism thus increasing the resistivity. A similar behavior was reported in case of Ni-Al ferrite system [23] and Bi2O3 doped CoFe2O4…

    • 1962 Words
    • 8 Pages
    Improved Essays
  • Superior Essays

    Positive ions are attracted to the negative electrode, gain electrons so are reduced. This is…

    • 1162 Words
    • 5 Pages
    Superior Essays
  • Improved Essays

    Since elevated temperature makes a metal more active, it will become anodic for rest of the metal. So an electrochemical corrosion cell might cause fast corrosion on metals that are at elevated temperatures. 2) pH of the Electrolyte The ph of the electrolyte in an electrochemical corrosion cell affects the speed of the corrosion by speeding up or slowing down the chemical reactions at the anode and/or the cathode. The ph of an electrolyte is basically the concentration of hydrogen ions. A ph.…

    • 1106 Words
    • 5 Pages
    Improved Essays
  • Improved Essays

    Action Potential Essay

    • 766 Words
    • 4 Pages

    When the action potential reaches its peak of 30 millivolts, Na+ channels close. Repolarization begins as K+ voltage gated channels start to open and an efflux of K+ are driven out of the cell due to the electrochemical gradient. With less Na+ inside the cell and more K+ outside the cell, the membrane potential begins to decline toward its resting value. Resting value is reached, yet K+ voltage gated channels remain open allowing additional K+ to move out. Hyperpolarization is activated when the K+ gates finally close and the membrane potential is now more negatively charged than at resting value due to the imbalance of ions inside and outside the cell.…

    • 766 Words
    • 4 Pages
    Improved Essays