BIO 202 STRAIGHTERLINE CHAPTER 20 WITH 100- CORRECT ANSWERS

the major functions of the heart: -generation of blood pressure -routing of the blood -ensuring one-way blood flow -regulation of the blood supply The adult heart is roughly the size of clenched fist an average mass of 250g in females, 300 g in males the rounded point of the heart is called the apex the larger, flat part of the heart is called the base The heart is located in the Mediastinum of the thoracic cavity Effective cardiopulmonary resuscitation also depends on a reasonable knowledge of the position of the heart. pericarditis inflammation of the pericardium cardiac tamponade is a potentially fatal condition in which a large volume of fluid or blood accumulates in the pericardial cavity and compresses the heart from the outside. pericardium (pericardial sac) is a double-layered, closed sac that surrounds the heart. It consists of the fibrous pericardium and the serous pericardium. the pericardium consists of two layers: outer fibrous pericardium nd inner serous pericardium parietal pericardium outer layer of the pericardium visceral pericardium (epicardium) covers the heart's outer surface (ON the surface) pericardial cavity surrounds the heart pericardial fluid serous fluid between parietal & visceral pericardium; reduces friction when heart beats The heart wall is composed of three layers of tissue (1) the epicardium, (2) myocardium, and (3) endocardium The epicardium or visceral pericardium is the superficial layer of the heart wall. It is a thin serous membrane that constitutes the smooth, outer surface of the heart. The myocardium is the thick, middle layer of the heart. It is composed of cardiac muscle cells and is responsible for the heart's ability to contract. The endocardium is deep to the myocardium. It consists of simple squamous epithelium over a layer of connective tissue. pectinate muscles internal ridges of myocardium in right atrium and both auricles crista terminalis C-shaped ridge landmark used to locate veins entering right atrium trabeculae carneae muscular ridges on the internal surface of the ventricles the heart wall consists of four chambers: two atria two ventricles Auricles "flaps" on the atria to increase the volume of the chamber superior vena cava A vein that is the second largest vein in the human body and returns blood to the right atrium of the heart from the upper half of the body. inferior vena cava A vein that is the largest vein in the human body and returns blood to the right atrium of the heart from bodily parts below the diaphragm. Four pulmonary veins carry blood from the lungs to the left atrium blood leaves the ventricles of the heart through two arteries: the pulmonary trunk the aorta the pulmonary trunk carries blood from right ventricle to pulmonary arteries the aorta carries blood from the left ventricle to the body coronary sulcus groove that marks border between atria and ventricles anterior interventricular sulcus marks the boundary between the ventricles anteriorly posterior interventricular sulcus marks the boundary between the ventricles posteriorly The first major branch of the left coronary artery is the anterior interventricular artery, or the left anterior descending artery. It extends inferiorly in the anterior interventricular sulcus and supplies blood to most of the anterior part of the heart. The second major branch of the left coronary artery is the left marginal artery, which supplies blood to the lateral wall of the left ventricle. The third major branch of the left coronary artery is the circumflex artery, which extends around to the posterior side of the heart in the coronary sulcus. Branches of the circumflex artery supply blood to much of the posterior wall of the heart. A larger branch of the right coronary artery called the right marginal artery, and other branches supply blood to the lateral wall of the right ventricle. A second branch of the right coronary artery, called the posterior interventricular artery, lies in the posterior interventricular sulcus and supplies blood to the posterior and inferior part of the heart. anastomoses a connection between two blood vessels or tubes A small cardiac vein drains the right margin of the heart & The great cardiac vein drains blood from the left side of the heart and converge toward the posterior part of the coronary sulcus that empty into a large venous cavity called the coronary sinus, which in turn empties into the right atrium.