what you need to know about your heart
The heart is the body's engine room, responsible for pumping life-sustaining blood via a 60,000-mile-long (97,000-kilometer-long) network of vessels, that's long enough to circle the Earth two and a half times!
Made up of a special kind of muscle (cardiac muscle), the heart works ceaselessly and involontary, so we don't have to think about it. The heart speeds up or slow downs automatically in response to nerve signals from the brain that tell it how much the body is being exerted. The heart rate is measured in beats by munites (BPM), varies depending on person’s level of stress and physical activity
Your Heart beats 100,000 times a day, 40 million times a year—in total clocking up three billion heartbeats over an average lifetime to keep the body freshly supplied with oxygen and nutrients, while clearing away harmful waste matter.Normally the heart contracts and relaxes between 70 and 80 times per minute, each heartbeat filling the four chambers inside with a fresh round of blood.
For your heart to keep pumping regularly, it needs an electrical supply. This is provided by a special group of heart cells called the sinus node, which is also known as your heart’s natural pacemaker.
These cavities form two separate pumps on each side of the heart, which are divided by a wall of muscle called the septum. The upper chamber on each side is called the atrium. This is connected via a sealing valve to the larger, more powerful lower chamber, or ventricle. The left ventricle pumps most forcefully, which is why a person's heartbeat is felt more on the left side of the chest.
The Heart, the center of life
Since the heart lies at the center of the blood delivery system, it is also central to life. Blood both supplies oxygen from the lungs to the other organs and tissues and removes carbon dioxide to the lungs, where the gas is breathed out. Blood also distributes nourishment from the digestive system and hormones from glands. the heart circulates nearly two galons (5 liters ) of blood through the body
the heart is also important in our immune system since the cells travel in the bloodstream, seeking out infection, and blood takes the body's waste products to the kidneys and liver to be sorted out and trashed.
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