File Name: heart parts and functions .zip
The cardiovascular system can be thought of as the transport system of the body.
The human heart is a finely-tuned instrument that serves the whole body. It is a muscular organ around the size of a closed fist, and it sits in the chest, slightly to the left of center.
The heart: All you need to know
The heart is the hardest working muscle in the human body. Located almost in the center of the chest, a healthy adult heart is the size of a clenched adult fist. The heart is always working. A child's heart works just as hard as an adult's heart. An adult's heart often beats between 60 and times a minute.
The heart has 4 chambers, 2 upper chambers atria and 2 lower chambers ventricles. Blood passes through a valve before leaving each chamber of the heart. The valves prevent the backward flow of blood. Valves are actually flaps leaflets that act as one-way inlets for blood coming into a ventricle and one-way outlets for blood leaving a ventricle. Normal valves have 3 flaps leaflets , except the mitral valve. It only has 2 flaps. The 4 heart valves are:.
Blood must always circulate to sustain life. It carries oxygen from the air we breathe to cells throughout the body. The pumping of the heart drives this blood flow through the arteries, capillaries, and veins. One set of blood vessels circulates blood through the lungs for gas exchange. The other vessels fuel the rest of the body. Read on to learn more about these crucial circulatory system functions.
Anatomy and Function of the Heart Valves
The cardiovascular system is a closed system if the heart and blood vessels. The heart pumps blood through a closed system of blood vessels. Blood vessels allow blood to circulate to all parts of the body. The vital importance of the heart is obvious. If one assumes an average rate of contraction of 75 contractions per minute, a human heart would contract approximately , times in one day, more than 39 million times in one year, and nearly 3 billion times during a year lifespan.
Your heart does a lot of work to keep the body going. Each day, the average human heart beats about , times, pumping 2, gallons of blood through the body. In fact, the heart does more physical work than any other muscle over a lifetime. Located between the lungs in the middle of the chest, the heart pumps blood through the network of arteries and veins known as the cardiovascular system.
The heart itself is made up of 4 chambers, 2 atria and 2 ventricles. De-oxygenated blood returns to the right side of the heart via the venous circulation. It is pumped into the right ventricle and then to the lungs where carbon dioxide is released and oxygen is absorbed.
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