The inferior tip of the heart, known as the apex, rests just superior to the diaphragm. Anatomy of the Heart Pericardium The heart sits within a fluid-filled cavity called the pericardial cavity. The walls and lining of the pericardial cavity are a special membrane known as the pericardium. Pericardium is a type of serous membrane that produces serous fluid to lubricate the heart and prevent friction between the ever beating heart and its surrounding organs.
Print Anatomy of the Heart The heart is the hollow, muscular organ in the thoracic cavity chest that maintains the circulation of blood throughout the body.
It is surrounded by a membrane called the pericardium. The pericardium consists of a layer of fibrous connective tissue and a layer of thin, serous i.
This fluid prevents friction between the pericardium and the heart. The heart wall consists of the epicardium inner layerthe myocardium middle layer comprised of cardiac muscle tissueand the endocardium lining of the myocardium that covers the heart valves.
The heart has a right side and a left side. Each side has a relatively thin-walled chamber that receives blood returning to the heart atrium and a muscular chamber that pumps blood out of the heart ventricle.
Blood Flow The flow of blood through the heart is controlled by the opening and closing of valves and the contraction and relaxation of the myocardium. Heart valves are controlled by pressure changes within each chamber and contraction and relaxation are controlled by the heart's conduction system.
Blood that has traveled through the body returns to the heart and enters the right atrium. This blood flows through the tricuspid valve into the right ventricle. The right ventricle pumps the blood to the lungs, where it absorbs oxygen.
Oxygen-rich blood returns from the lungs and enters the heart through the left atrium. Blood passes from the left atrium through the mitral valve and into the left ventricle. The left ventricle, the largest and most muscular of the four chambers, is the main pumping chamber of the heart.
When the left ventricle contracts, blood is pumped through the aortic valve into the main artery of the body aorta. The aorta supplies blood to smaller arteries that travel to the head, arms, abdomen, and legs.
These arteries supply oxygen-rich blood to the organs and tissues of the body, which require oxygen to function. The coronary arteries supply oxygen-rich blood to the tissues of the heart.
Oxygen-poor blood travels from organs and tissues to the heart through veins. The vena cava is the major vein that returns blood to the right atrium of the heart.
The vena cava superior returns blood from the head, neck, upper extremities, and chest. The vena cava inferior returns blood from the lower extremities, the pelvis, and the abdomen.
The coronary sinus drains blood from the coronary arteries into the right atrium. Conduction System An electrical impulse travels through the heart and initiates contractions of the chambers.
The heart's "spark plug" is an area of specialized heart tissue called the sinoatrial node SA nodewhich is located in the right atrium. Each time the SA node "fires," an electrical impulse is generated that travels through the right and left atria, signaling these chambers to contract and pump blood into the ventricles.
The impulse then travels into another area of specialized heart tissue called the atrioventricular node AV nodewhich is located between the atria and the ventricles. The electrical impulse is conducted through the AV node and wire-like pathways Purkinje fibers to the ventricles, signaling the ventricles to contract and pump blood into the lungs and throughout the body.
The normal sequence of electrical activation of the chambers of the heart is called sinus rhythm. It occurs each time the heart beats, usually about 60 to 80 times every minute. In a normal heartbeat, the atria contract simultaneously while the ventricles relax.
Then, the ventricles relax and the atria contract. The term systole refers to contraction and the term diastole refers to relaxation.
A heartbeat consists of the systole and diastole of the atria and the systole and diastole of the ventricles.Blood is a constantly circulating fluid providing the body with nutrition, oxygen, and waste removal. Blood is mostly liquid, with numerous cells and proteins suspended in it, making blood.
Heart chambers and associated great vessels. The heart has four chambers – two superior atria and two inferior alphabetnyc.com internal partition that divides the heart longitudinally is called the interatrial septum where it separates the atria, and the interventricular septum where is separates the ventricles.
The right ventricle forms most of the anterior surface of the heart. Leukemia: A form of blood cancer, in which white blood cells multiply abnormally and circulate through the blood.
The abnormal white blood cells make getting sick from infections easier than normal. The Anatomy of the Heart By Wendy Dusek.
In this animated and interactive object, learners identify the valves and chambers of the heart. Heart chambers and associated great vessels. The heart has four chambers – two superior atria and two inferior alphabetnyc.com internal partition that divides the heart longitudinally is called the interatrial septum where it separates the atria, and the interventricular septum where is separates the ventricles.
The right ventricle forms most of the anterior surface of the heart, while the. The heart is a mostly hollow, muscular organ composed of cardiac muscles and connective tissue that acts as a pump to distribute blood throughout the body’s tissues.