ATTR 219 Lecture 3Layers of Heart-heart wall composed of three layers of tissue1. Epicardium (outer layer)-thin protective membrane that contains blood vessels that nourish the heart wall2. Myocardium-Forms bulk of heart wall and is composed of cardiac muscle tissue – provides contractions to eject blood from heart throughout body-needs continuous supply of oxygen and nutrients unlike skeletal and smooth muscle-lack of oxygen would lead to a heart attack or cardiac arrest3. Endocardium- smooth membrane lining chambers of heart- allows for smooth blood flow through the heart-bacterial infections in endocardium can be deadlyChambers of the Heart- 4 chambers in the heart- left & right ventricleleft &right atria- 2 atria are thin walled and receive blood from the body- 2 ventricles are thick and pump blood out to the body - Both atria and ventricles are separated by septumProcess of Flow of Blood Through the Heart-inferior and superior vena cova return blood to right atrium (inferior takes blood from lower extremities to heart, superior takes blood from upper extremity to the heart)- blood is shunted to right ventricle from right ventricle from right atria (must first pass through tricuspid valve)-blood is sent to lungs from right centricle to be oxygenated via the pulmonary arteries (only place in arteries where there is unoxygenated blood)-blood oxygenated in lungs and returned to heart via pulmonary veinsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.-blood returned to left atrium from pulmonary veins-left ventricle receives blood from left atrium (must first pass through bicuspid valve)-blood is then pumped out to body going first to aorta*Blood flow handout online*-entire process of oxygen and nutrient breakdown is known as perfusion-Perfusion-process of blood entering an organ/tissue through arteries, leaving through veins while providing nourishment and removing wasteConduction System of the Heart-atria THEN ventricles contract- not simultaneously 1st part of conduction system:- Sinoatrial (SA) node- right atrium- 70-80 simultaneous atrial contractions per min (pacemaker of the heart)2nd part of conduction system:- Atrioventricular (AV) node- also in right atriumValves-Atrioventricular valves (same as bicuspid and tricuspid valves)- located between atria and ventricles-Semilunar valves- located between ventricles and large vessels- all are one way valvesBlood Vessels of BodyArteries-carry blood away from heart out to vital organs- composed of 3 layers and hollow core known as lumen-two major properties of arteries are elasticity and contractibility-arteries branch off to form smaller arteriolesArterioles-assist in regulating blood flow from arteries to capillaries- bridge from arteries to capillary beds-60,000 miles of blood vessel on average per personArteries of Head and Upper Extremity - Brachiocephalic- Carotid- Subclavian- Vertebral- Ulnar- Brachial- RadialArteries of Abdominal Viscera- Intercostals-ribs- Bronchial- lungs- Celiac- mid upper abdomen- Hepatic-liver- Mesenteric- Lumbar- lower back- Renal- kidneysArteries of Lower Extremity - Right and left iliac- Femur- Popliteal- posterior aspect of knee- Posterior tibial- between gastrock heads- Dorsalis pedis (dorsal pedal)- top of foot (farthest detectable pulse from heart)Veins- Carry blood from body back to heart- Thinner walled than arteries- Have one way valves- when these valves breakdown it produces backflow which results in varicose veins- Great saphenous vein in lower extremity - Veins branch off to form venulesCapillaries -microscopic vessels that connect arterioles and venules- exchange of nutrients and wastes between blood and tissuesStructures with many capillaries include:- Skeletal muscle- Kidneys- LiverStructures with no capillaries include:- Epidermis- Cornea and lens of the eye- Cartilage-Components of Blood-plasma- liquid portion of the blood- straw colored and made up of about 90% of waterErythrocytes (Red Blood Cells)- before birth are manufactured in spleen and liver, after birth are manufactured in bone marrowHemopoiesis- process by which blood cells are produced in the bodyLeukocytes (White Blood Cells)- neutrophils, eosinophils, basophils, lymphocytes- body’s defense againstorganismsPlatelets- responsible for clotting/coagulation- invade damaged tissue and adhere to the wound and each