Test: Difference between revisions

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==The ECG represents the sum of the action potentials of millions of cardiomyocytes==
==The ECG represents the sum of the action potentials of millions of cardiomyocytes==
The individual [[action potential|action potentials]] of the individual cardiomyocytes are averaged. The final result which is shown on the ECG is actually the average of trillions of microscopic electronical signals.
[[Image:Ion_currents_en.png|thumb|right|300px|During the depolarization sodium-ions stream inwards the cell. Subsequently the calcium-ions stream into the cell. These calcium-ions give the actual muscular contraction. Finally the potassium-ions stream out of the cell. During the repolarisation the ion concentration is corrected. On the ECG, an action potential wave coming towards the electrode is shown as a positive (upwards) signal. Here the ECG electrode is represented as an eye.]]
[[Image:Ion_currents_en.png|thumb|right|300px|During the depolarization sodium-ions stream inwards the cell. Subsequently the calcium-ions stream into the cell. These calcium-ions give the actual muscular contraction. Finally the potassium-ions stream out of the cell. During the repolarisation the ion concentration is corrected. On the ECG, an action potential wave coming towards the electrode is shown as a positive (upwards) signal. Here the ECG electrode is represented as an eye.]]
[[Image:Hart_cells_en.png|thumb|left|280px|The heart consists of approximately 300 trillion cells]]
[[Image:Hart_cells_en.png|thumb|left|280px|The heart consists of approximately 300 trillion cells]]
[[Image:cells_in_rest_en.png|thumb|left|280px|In rest the heart cells are negatively charged. Through the depolarization by surrounding cells they become positively charged and they contract.]]
[[Image:cells_in_rest_en.png|thumb|left|280px|In rest the heart cells are negatively charged. Through the depolarization by surrounding cells they become positively charged and they contract.]]
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The individual [[action potential|action potentials]] of the individual cardiomyocytes are averaged. The final result which is shown on the ECG is actually the average of trillions of microscopic electronical signals.


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==The electric discharge of the heart==
==The electric discharge of the heart==
[[Image:conduction_system_en.png|thumb|left|250px]]
[[Image:conduction_system_en.png|thumb|left|250px]]
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