Basics: Difference between revisions

4 bytes removed ,  19 September 2006
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[[Image:Hart_cells.png|thumb|The heart consists of approximately 300 trillion cells]]
[[Image:Hart_cells.png|thumb|The heart consists of approximately 300 trillion cells]]
[[Image:cells_in_rest.png|thumb|In rest the heart cells are negatively charged. Trough the depolarization by surrounding cells they become positively charged and they contract.]]
[[Image:cells_in_rest.png|thumb|In rest the heart cells are negatively charged. Trough the depolarization by surrounding cells they become positively charged and they contract.]]
[[Image:Ion_currents.jpg|thumb|During the depolarization sodium-ions stream inwards the cell. Subsequently the calcium-ions stream inwards 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 you is shown as a positive result. The ECG electrode is represented here as an eye.]]
[[Image:Ion_currents.jpg|thumb|During the depolarization sodium-ions stream inwards the cell. Subsequently the calcium-ions stream inwards 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 is shown as a positive result. Here the ECG electrode is represented as an eye.]]
The individual [[action potential|action potentials]] of the individual cardiomyocytes are in fact averaged. The final result is actually the average of trillions of microscopic electronical signals
The individual [[action potential|action potentials]] of the individual cardiomyocytes are in fact averaged. The final result is actually the average of trillions of microscopic electronical signals
{{clr}}
{{clr}}