What is the importance of cardiac muscles in the rhythmic contraction and relaxation of heart?

Asked by  | 28th Aug, 2012, 08:21: PM

Expert Answer:

The heart is composed of cardiac muscle tissue that is very strong and able to contract and relax rhythmically throughout a person's lifetime.
A network of nerve fibers coordinates the contraction and relaxation of the cardiac muscle tissue to obtain an efficient, wave-like pumping action of the heart. Cardiac muscle fibres are interconnected in branching networks that spread in all directions through the heart. This allows an impulse travels to all parts of the heart when any portion of this net is stimulated. The whole structure contracts as a unit in a wave-like manner. Cardiac muscle cells are also connected by specialized regions of membrane called intercalated discs. These discs increase the surface area connecting two cells and reduce the electrical resistance between cells, thus allowing them to act more as one unit. 
In addition, tre clumps and strands of specialized cardiac muscle tissue e not designed for contraction, but instead they initiate and distribute impulses (cardiac impulses) through the myocardium. They are the cardiac conduction system, which functions to coordinate the events occurring during the cardiac cycle.

Answered by  | 29th Aug, 2012, 10:38: AM

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