Logged out
Access All our Essays in an Instant
Swap your work for FREE access, or pay £4.99 for instant access
How the heart works
Member rating: No Rating | Words: | Submitted: Tue Aug 19 2003
Page Preview
On the left is an image preview of every page of this document, and below are the first 150 words with formatting removed:
How the heart works The cardiac electrical system The heart generates its own electrical signal, or impulse. This electrical impulse can be recorded by placing electrodes on the skin of the chest, thus producing the electrocardiogram (ECG, or EKG). The heart's electrical impulse arises in the upper portion of the right atrium and spreads across. As it spreads, it triggers the heart muscle to contract in a coordinated fashion. If the electrical signal becomes deranged in some way, the efficient pumping action of the heart may deteriorate, or stop altogether. The components of the heart's electrical system are illustrated here. From an electrical standpoint, the heart is divided into two portions - the atria, and the ventricles. Separating the atria from the ventricles is a non-muscular, fibrous "disc." This disc (labeled AV disk in the figure,) prevents the passage of the electrical signal between the atria and the ventricles. In this...
Get instant access
- Instant, unlimited access to our documents in full
- Swap your work for free access, or pay £4.99
- To see the full version of this document and 151,713 others
