explanation on heart
Answers
hey mate...
here is your answer...
The heart is responsible for circulating blood throughout the body. It is about the size of your clenched fist and sits in the chest cavity between your two lungs. Its walls are made up of muscle that can squeeze or pump blood out every time the heart "beats" or contracts. Fresh, oxygen-rich air is brought into the lungs every time you take a breath. The lungs are responsible for delivering oxygen to the blood, and the heart circulates the blood through the lungs and out to the different parts of the body.
The heart is divided into four chambers or "rooms". You can compare it to a duplex apartment that is made up of a right and a left unit, separated from each other by a partition wall known as a septum (pronounced SEP-tum).
Each "duplex" is subdivided into an upper and a lower chamber. The upper chamber is known as the atrium (pronounced AY-tree-yum) while the lower chamber is referred to as the ventricle (pronounced VEN-trickle). The right atrium (RA) sits on top of the right ventricle (RV) on the right side of the heart while the left atrium (LA) sits atop the left ventricle (LV) on the left side.
The right side of the heart (RA and RV) is responsible for pumping blood to the lungs, where the blood cells pick up fresh oxygen. This oxygenated blood is then returned to the left side of the heart (LA and LV). From here the oxygenated blood is pumped out to the rest of the body supplying the fuel that the body cells need to function. The cells of the body remove oxygen from the blood, and the oxygen-poor blood is returned to the RA, where the journey began. This round trip is known as the circulation of blood. Do you wonder why each side of the heart has two pumping chambers (atrium and ventricle)? Why not just have a ventricle to receive blood and then pump it straight out? The reason is that the atrium serves as a "booster pump" that increases the filling of the ventricle. Filling a normal ventricle to capacity translates to more vigorous contraction or emptying. You can compare this to a strong spring. Within reasonable limits, the more you stretch a spring, the more vigorously will be its contraction or recoil. More complete filling of the ventricles thus translates into more vigorous ventricular contraction (a good thing).
hope it helps...
please mark as the brainliest...