How does the heart keep besting?
The human heart beats without stopping for an average of 70 year,pumping a total of about 180 million litres of blood throught the body. This impressive performance is made possible by a special kind of muscle that exists in the heart alone . It is called the myocardial,or heart, muscle and it combines the properties of two other kinds of muscle found elsewhere in the body, striated muscle and smooth muscle. Striated muscles, like those found in the arm and leg, are voluntary muscles; they move quickly and on command but also tire quickly. Smooth muscles, like those in stomach and intestines , are involuntary ; they cannot be moved at will and are tireless. The heart muscle is both involuntary and striated. It constantly keeps the heart beating, but can change the pace for short periods when needed
How does the heart keep besting?The human heart beats without stopping for an average of 70 year,pumping a total of about 180 million litres of blood throught the body. This impressive performance is made possible by a special kind of muscle that exists in the heart alone . It is called the myocardial,or heart, muscle and it combines the properties of two other kinds of muscle found elsewhere in the body, striated muscle and smooth muscle. Striated muscles, like those found in the arm and leg, are voluntary muscles; they move quickly and on command but also tire quickly. Smooth muscles, like those in stomach and intestines , are involuntary ; they cannot be moved at will and are tireless. The heart muscle is both involuntary and striated. It constantly keeps the heart beating, but can change the pace for short periods when needed
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