Nu LiPa Cardiovascular System PDF

CARDIOVASCULAR SYSTEM PARTS OF CARDIOVASCULAR SYSTEM The heart is approx. the size of a closed fist and is located in the pericardial cavity. CIRCULATORY SYSTEM HEART Functions: 1. Generating blood pressure- through contractions...

CARDIOVASCULAR SYSTEM PARTS OF CARDIOVASCULAR SYSTEM The heart is approx. the size of a closed fist and is located in the pericardial cavity. CIRCULATORY SYSTEM HEART Functions: 1. Generating blood pressure- through contractions 2. Routing blood- oxygenated and deoxygenated blood pathways 3. Ensuring one-way blood flow 4. Regulating blood supply- matches flow to the changing metabolic needs of the tissues SIZE, FORM AND LOCATION OF HEART Apex- blunt, rounded point of the heart Base- larger, flat part of the opposite end of the heart Pericardial cavity- surrounding cavity of the heart Importance of location and shape of the heart -to accurately place a stethoscope -to place chest leads for ECG -to administer CPR HEART CHAMBERS AND INTERNAL ANATOMY Right and Left Atria -receives blood from the veins -Function as reservoir, where blood returning from veins collects before it enter the ventricles Interatrial septum- separator of the two atria Right and Left Ventricle -Major pumping chambers -ejects blood into the arteries and forces it to flow through the circulatory system Interventricular septum- separator of the two ventricles HEART VALVES Atrioventricular Valves- allows blood to flow from the atria into the ventricles, prevents it from flowing back into the atria 1. Tricuspid valve- between the Right Atrium and Right Ventricle 2. Bicuspid/Mitral Valve- between the left atrium and left ventricle Supporting Valves Papillary Muscles- cone-shaped, muscular pillars; prevents the valves from opening into the atria Chordae tendineae- thin, strong, connective tissue strings Aortic and Pulmonary Semilunar valves- blocks blood from flowing back into the ventricles ROUTE OF BLOOD FLOW THROUGH THE HEART BLOOD FLOW THROUGH THE HEART BLOOD SUPPLY TO THE HEART Coronary arteries- supply blood to the wall of the heart HISTOLOGY OF THE HEART Heart Wall 1. Epicardium/Visceral Pericardium -thin, serous membrane forming the smooth outer surface -consists of simple squamous epithelium overlaying a layer of loose connective tissue + adipose tissue 2. Myocardium -composed of cardiac muscles -responsible for contraction of the heart chambers 3. Endocardium -simple squamous epithelium over a layer of connective tissue -allows blood to move easily -forms the heart valves 4. Trabeculae Carneae -ridges and columns of cardiac muscle CONDUCTION SYSTEM OF THE HEART Sinoatrial (SA) node- heart’s pacemaker, initiates the contraction of the heart Atrioventricular (AV) node- spreads action potential slowly Atrioventricular bundle of specialized cardiac muscles Left and Right bundle branches- two branches of conducting tissue Purkinje Fibers- conduct action potentials more rapidly that CARDIAC CYCLE ATRIUM- primer pump, complete the filling of ventricles with blood VENTRICLE- power pump, produce the major force that causes blood to flow ATRIAL SYSTOLE- contraction of two atria VENTRICULAR SYSTOLE- Contraction of two ventricles ATRIAL DIASTOLE- relaxation of the two atria VENTRICULAR DIASTOLE- relaxation of the two ventricles HEART SOUNDS LUBB- closure of the AV valves DUBB- closure of the semilunar valves MURMURS- abnormal heart sounds Heart Rate- number of times the heart contracts per minutes; Normal HR: 60-100 beats per minute BLOOD VESSELS Function: 1. Carries blood- from the heart to all tissues 2. Exchanges nutrients, products and gases with tissues 3. Transports substances (hormones, molecules) 3TYPES OF BLOOD VESSELS 1. ARTERIES- carry blood away from the heart (oxygenated blood) AORTA- largest artery 2. VEINS- Carry blood toward the heart (deoxygenated blood) VENA CAVA- largest vein 3. CAPILLARIES- smallest blood vessel -Principal function: nutrient and waste exchange Major Arteries of the body Major veins of the body