19-07-2011, 12:19 PM
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Bioelectricity
Bioelectricity is used by biological cells to store energy.
We can lift a finger due to bioelectricity. Almost every action is done due to the existence of bioelectricity. We are talking about electrical signals that are generated and detected by our organs, muscles, brain, and glands. These signals are as well transmitted by our nerves.
Our body is built with biological tissue. The tissue that can generate or detect bioelectrical signals is called excitable tissue. Some examples of this tissue (and its cells) are: neurons and muscular tissue. Neurons are responsible of transmitting the excitatory bioelectrical signal to another neuron (forming nerves) or to a muscle tissue, while muscular cells are responsible of muscular contraction and distension. Some specialized cells generate bioelectric signals: optic receptors (eyes), muscular cells that transmit the feeling of pain, etc.
• Bioelectricity (sometimes equated with bioelectromagnetism) refers to the electrical, magnetic or electromagnetic fields produced by living cells, tissues or organisms.
• Biological cells use bioelectricity to store metabolic energy, to do work or trigger internal changes.
• Bioelectricity is the electric current produced by action potentials along with the magnetic fields they generate through the phenomenon of electromagnetism.
Ionic equilibrium
Ionic concentration inside and outside the neuron is not symmetric. This leads to a concentration gradient and furthermore electric gradient. This means that there is an equilibrium voltage different than 0 V between the intra-cellular medium and extra-cellular medium, for each kind of existing ion.
There are four main ions involved in this process: Sodium (Na), Potassium (K), Chlorine (Cl) and Calcium (Ca). Each of them has different permittivity (equivalent to conductance) through soma membrane and different equilibrium potential.
The existence of different equilibrium potentials (constant) and varying permittivity let us model the neuron membrane as an electrical circuit as shown in the next picture. CM is the capacitance of the neuron where the membrane is the dielectric.
Bioelectricity
Bioelectricity is used by biological cells to store energy.
We can lift a finger due to bioelectricity. Almost every action is done due to the existence of bioelectricity. We are talking about electrical signals that are generated and detected by our organs, muscles, brain, and glands. These signals are as well transmitted by our nerves.
Our body is built with biological tissue. The tissue that can generate or detect bioelectrical signals is called excitable tissue. Some examples of this tissue (and its cells) are: neurons and muscular tissue. Neurons are responsible of transmitting the excitatory bioelectrical signal to another neuron (forming nerves) or to a muscle tissue, while muscular cells are responsible of muscular contraction and distension. Some specialized cells generate bioelectric signals: optic receptors (eyes), muscular cells that transmit the feeling of pain, etc.
• Bioelectricity (sometimes equated with bioelectromagnetism) refers to the electrical, magnetic or electromagnetic fields produced by living cells, tissues or organisms.
• Biological cells use bioelectricity to store metabolic energy, to do work or trigger internal changes.
• Bioelectricity is the electric current produced by action potentials along with the magnetic fields they generate through the phenomenon of electromagnetism.
Ionic equilibrium
Ionic concentration inside and outside the neuron is not symmetric. This leads to a concentration gradient and furthermore electric gradient. This means that there is an equilibrium voltage different than 0 V between the intra-cellular medium and extra-cellular medium, for each kind of existing ion.
There are four main ions involved in this process: Sodium (Na), Potassium (K), Chlorine (Cl) and Calcium (Ca). Each of them has different permittivity (equivalent to conductance) through soma membrane and different equilibrium potential.
The existence of different equilibrium potentials (constant) and varying permittivity let us model the neuron membrane as an electrical circuit as shown in the next picture. CM is the capacitance of the neuron where the membrane is the dielectric.
