Human Anatomy Lab 6 PDF

Al-Noor University Anatomy Lab. First stage of dentistry Assistant Lecturer : Bushra Saeed Human Anatomy Anatomy of heart and major Arteries and Veins The heart The heart is muscular organ in circulatory system that is responsible for pu...

Al-Noor University Anatomy Lab. First stage of dentistry Assistant Lecturer : Bushra Saeed Human Anatomy Anatomy of heart and major Arteries and Veins The heart The heart is muscular organ in circulatory system that is responsible for pumping blood throughout the blood vessels to our body. Size and location of The heart Approximately the size of a persons fist. Location  Thorax, between the lungs  Superior surface of diaphragm  Left of the midline  Anterior to the vertebral column, posterior to the sternum Coverings of the Heart Pericardium – a double-walled sac around the heart composed of: A superficial fibrous pericardium A deep two-layer serous pericardium a. The parietal layer b. The visceral layer They are separated by the fluid-filled pericardial cavity The Function of the Pericardium:  Protects the heart.  Prevents overfilling of the heart with blood.  Allows for the heart to work in a relatively friction-free environment.  Wall of heart: Composed of 3 layers:  Epicardium: visceral layer of the serous pericardium  Myocardium: Middle layer composed of cardiac muscle and responsibility for heart contracting.  Endocardium: Smooth inner surface of heart chambers  Chambers The heart have four chambers:  Two Atria (Left atrium and right atrium) ( Receving chambers)  Two ventricles (Left ventricle and right ventricle) (Discharging chambers).  Left and right atrium are separated by interatrial septum  Left and right ventricle are separated by interventricular septum.  Valves The heart have four valves.  The function of this valves is allow blood to flow in only one direction and present back flow into the atria when the ventricles contract. Types of valves: A- Atrioventricular valves:  Bicuspid valve: Separates the left atrium from the left ventricle.  Tricuspid valve: Separates the right Bicuspid atrium from the right ventricle. B- Semilunar valves:  Aortic valve: Separates the left ventricle from the aorta.  Pulmonary valve: Separates the right ventricle from the pulmonary artery.  Blood vessels:  Arteriesarterioles : Which carry oxygen rich blood away from heart to body.  VeinsVenules : Which carry oxygen poor blood to heart away from the body.  Capillaries: Smallest vessels, where gas exchange takes place.  Major Vessels of the Heart Vessels returning blood to the heart include: Superior vena cava inferior vena cava Right pulmonary vein left pulmonary vein Vessels carrying blood away from the heart include: Pulmonary trunk, which splits into right and left pulmonary arteries. aorta (three branches): a. Brachiocephalic artery b. Left common carotid artery c. Left Subclavian artery Aorta :is the largest artery of the body ,carries oxygenated blood from Lt ventricle ,arise from base of Lt ventricle.it has 3 segment –Ascending aorta -Arch of aorta –brachiocephalic trunk -Lt common carotid artery -Lt subclavian artery -Descending aorta – pass through diaphragm into abdomen Pulmonary artery(trunk): *carry deoxygenated systemic blood from Rt ventricle of the heart to the lungs. *It bifurcate into Rt and Lt pulmonary arteries below the arch of aorta. *The Lt pul.artery is shorter than the Rt. Pulmonary veins : *Receive oxygenated blood from the lungs to the Lt atrium and Lt ventricle ,to be pumped around the body. *There are 4 pulmonary veins ,two for each lung ,drain to the Lt atrium posteriorly. Blood supply of the heart (coronary circulation) Two major coronary arteries branch off from the aorta. -The right coronary artery: supplies the right atrium and right ventricle. Branches: -posterior descending artery, supplies the bottom of left ventricle and back of the septum. -marginal artery : -The left coronary artery: supplies left atrium and left ventricle Branches: -circumflex artery (supplies lt atrium ,side and back of lt ventricle. -left anterior descending artery. supplies the front and bottom of the left ventricle and the front of the septum.  Cardiac venous drainage: *Coronary sinus - Is the primary (largest) vein of cardiac venous circulation located on the posterior surface of the heart emptying into Rt atrium. Tributaries of coronary sinus : 1-great cardiac vein 2-middle cardiac vein 3-small cardiac vein Systemic circulation: Carries oxygenated blood from the heart to the body and returns deoxygenated blood back to the heart. It strats in the left ventricle the aorta systemic arteries systemic capillaries systemic veins superior and inferior vena cava ends in the right atrium. Pulmonary circulation: It strats in the right ventricle the pulmonary trunk pulmonary arteries pulmonary capillaries pulmonary veins ends in the left atrium.  Path of blood Vena cava (Deoxygenated blood). Right atrium (Deoxygenated blood. Right ventricle (Deoxygenated blood). Pulmonary artery(Deoxygenated blood) Lungs ( Mixed blood) Pulmonary vein (Oxygenated blood). Left atrium (Oxygenated blood). Left ventricle (Oxygenated blood). Aorta ( Oxygenated blood). Body capillaries (Mixed blood).