WELCOME

OBJECTIVES  To know the role played THE HUMAN HEART in human life.  To know the different parts and functions of the heart in its working.

INTRODUCTION The human heart is a primary shell with four cavities,or open spaces, that is filled with blood. Someothers says that the heart is a muscular organ located just to the left of the breast bone(sternum). It is about the size of your fist, and this amazing muscle pumps 4300 gallons of blood a day. Anyway the heart is a main part of the body which have the same importance of oxygen&water in our life.

ACKNOWLEDGEMENT We express my gratitudes to our I.T. teacher Mr.Samkutty who selected & gave title for this project.And I express my heartiest thanks to the people & institutions who had helped us in this project.

FUNCTIONS OF THE HEART Every cell in our body needs oxygen in order to live and function.The role of the heart is to deliver the oxygen-rich blood is delivered. The arteries are the passage ways through which the blood is delivered.The largest artery is the aorta,which branches off the heart and then divides into many smaller arteries.The veins carry the deoxygenated blood back to the lungs to pick up more oxygen,and then back to the heart once again. Blood flows continuously through the circulatory system,and the heart muscle is the pump which it all possible.

Main Parts Of The Human Heart

PARTS OF THE HEART & THEIR FUNCTIONS  VENTRICLES : The bottom two chambers.The right ventricle pumps blood to the lungs to pick up oxygen.The left ventricle pumps blood to the rest of the body & it is the strongest chamber.  ATRIA: The top two chambers that receives blood from the body or lungs.  VALVES: There are four valves in the heart that help to direct blood flow.As they open and close,the valves produce sounds that can be heard with a sthethoscope.The heart sounds can often tell your doctor about your heart’s function.

Pulmonary circulation is the movement of blood from the heart, to the lungs, and back to the heart again. This is just one phase of the overall circulatory system. The veins bring waste-rich blood back to the heart, entering the right atrium throughout two large veins called vena cavae. The right atrium fills with the waste-rich blood and then contracts, pushing the blood through a one-way valve into the right ventricle. The right ventricle fills and then contracts, pushing the blood into the pulmonary artery which leads to the lungs. In the lung capillaries, the exchange of carbon dioxide and oxygen takes place. The fresh, oxygen-rich blood enters the pulmonary veins and then returns to the heart, re-entering through the left atrium. The oxygen-rich blood then passes through a one-way valve into the left ventricle where it will exit the heart through the main artery, called the aorta. The left ventricle's contraction forces the blood into the aorta and the blood begins its journey throughout the body. The one-way valves are important for preventing any backward flow of blood. The circulatory system is a network of one-way streets. If blood started flowing the wrong way, the blood gases (oxygen and carbon dioxide) might mix, causing a serious threat to your body. You can use a stethoscope to hear pulmonary circulation. The two sounds you hear, "lub" and "dub," are the ventricles contracting and the valves closing. CIRCULATION THROUGH HEART