Lab 2 Heart Anatomy PDF

ANATOMY OF THE HEART Ch 30  HEART Cone shaped Size of a fist Less than a pound Sits within the mediastinum In between two lungs Vertebral column on back Sternum on the front  CARDIOVASCULAR SYSTEM...

ANATOMY OF THE HEART Ch 30  HEART Cone shaped Size of a fist Less than a pound Sits within the mediastinum In between two lungs Vertebral column on back Sternum on the front  CARDIOVASCULAR SYSTEM * Major function of heart is transport – Oxygen, digested food, cell wastes, electrolytes, hormones Muscular pump,Loading… cardiac muscle – Contraction forces the blood through the blood vessels One way valve  COVERINGS OF THE HEART: ANATOMY be the * can on * know this Picture midterm - any frictions heart we never want in the  COVERINGS OF THE HEART: ANATOMY Pericardium – a double wall fibro-serous sac around the heart composed of: - – A superficial fibrous pericardium – A deep two-layer serous pericardium – The parietal layer lines the internal surface of the fibrous pericardium – Loading… The visceral layer or epicardium lines the surface of the heart – They are separated by the fluid-filled pericardial cavity Pericarditis- Inflammation of pericardium due to adhesion between the serous pericardial layers interfere with heart movement  Heart membrane Heart membrane is double wall fibro-serous sac called pericardium on top of epicardium. The epicardium is a thin layer of connective tissue and fat, and serves as an additional layer of protection for the heart, under the pericardium. Myocardium- Middle layer. The myocardium is the muscle tissue of the heart, composed of cardiac muscle , which contract like other muscle cells, but also conduct electricity to coordinate contraction. Endocardium- Innermost layer. The endocardium is composed of endothelial cells which provide a smooth, non-adherent surface for blood collection and pumping / MEMBRANES OF THE HEART this won't be on the midterm  CHAMBERS OF THE HEART Four chambers. Two atria on the superior position. Two ventricles inferior position. bottom of the Interatrial septum the Apex = heart Interventricular septum Right - ventricle most- of the anterior surface - of the heart Left ventricle is the apex of the heart and dominates - the back surface of the heart - Two grooves on the boundaries of the four chambers: 1. The coronary sulcus – on the junction between atria and ventricle 2. The anterior interventricular septum – separating right and left ventricle  going to be dayganed Oxygenated a onthe mid term red = Arteries. Oxygenated  right atrium >- ventricles > right Veins > left atrium > - lung(Oxygenated left ventricles blood now > - pulmonary - - deoxygenated a I onlyinthe heart systeml Blue > - red > - Oxygenated Superior Inferior vena Cava bring in all deoxygenate blood deoxygenated blood to the heart that can be - Veins Carry pumped to the lung Inferior Cava-gets blood below diaphragm Superior Cava -> get blood from above diaphragm Order of blood Flow : Oxygen-poor Blood > - Superior 1 Inferior Vena Cava-> pulmightatrium -Tricuspid valueRihtventriclebod returns from the lungs to left the pulmonary veins > - atrium > - mitral value > - left ventricle > Aortic value - > - Aorta The Atrioventricular (AU) values prevent back flow of blood into the atria during Ventricular Contraction Cardiac A slow heart rate increases end diastolic Output - Volume stroke volume and force of Contraction , , The auricles can slightly increase blood volume in the ventricles by providing additional space for blood to fill before it is pumped into the ventricles. QRS Wave of ECG represents ventricular depolarization Pwave of ECG Atrial depolarization represents Stroke volume : amount of blood pumped out Ventricle in 1 minute by each Afterload : Back pressure exerted by arterial blood Pulmonary left blood from the to the veins Carry atrium Oxygenated of the heart. lungs  ATRIA: THE RECEIVING CHAMBERS red blood alls either carry Oz or CO2 through body the Receiving chambers of blood from circulation. They are small thin walled. Push blood minimally to go down to ventricle. Three veins to enter blood to right atrium - Superior vena cava - Returns blood from - body regions superior to the diaphragm Inferior vena cava – Returns blood from body - regions inferior diaphragm Coronary - sinus - Blood from myocardium  it deoxygen Loading… - j > - Front View  VENTRICLES: THE DISCHARGING CHAMBERS Front Make up most of the volume of heart. - Right ventricle dominates anterior surface and left ventricle dominates posterior surface ↳ back Actual pump of the heart Walls are very thick compare to the atria Right ventricle pumps blood into pulmonary trunk and left ventricle into aorta , the largest artery in the body arting Aorta-Largest Right ventricle to the lungs in the body Left ventricle to the body HEART VALVES, AV SL oeatum won't be ATRIOVENTRICULAR VALVE #  HEART VALVES, AV Heart valves ensure unidirectional blood flow through the heart Total of four valves. Two atrioventricular (AV) valves between atria and ventricular junctions prevent backflow into the atria when ventricles contract The parts/ flaps of the valves are made up of collagen cords called “chordae tendineae” or heart string. These strings work as a supports for the valves ( open like umbrella) Chordae tendineae anchor AV valves to papillary muscles from the inside surface of the heart HEART VALVES, AV  HEART VALVES (SL) Two semilunar (SL) valves between ventricles and big arteries like aortic and pulmonary. Aortic semilunar valve lies between the left ventricle and the aorta Pulmonary semilunar valve lies between the right ventricle and pulmonary trunk Semilunar valves prevent backflow of blood - into the ventricles and open and close in response to pressure in the ventricles Faulty valves can be replaced HEART VALVES, SL  BLOOD FLOW THROUGH THE HEART Two circuits: -right side 1. Pulmonary 2. Systemic - leftSide Equal vol. of blood pumps through both these circuits. Pulmonary circuits originates from right ventricle, doesn’t need to travel a lot to go to lungs and doesn’t need much pressure too for this short trip. Systemic circuit originates from left ventricle, need travelling all over the body and must need more pressure for this long trip. Wall of the left ventricle is 3X thicker than right one.  Side deoxygenated blood-Right Oxygenated blood = Left Side THE PULMONARY Pulmonary AND SYSTEMICside Systemic - left CIRCUITS ↑ S - Right  THE PULMONARY AND SYSTEMIC CIRCUITS Right side of the heart receives O2 poor blood from all over the body and pumps to the lungs to pick up O2 and drop CO2. The blood vessels that carry blood to and from the lungs are called “pulmonary circuit” Right-pulmonary Left side of the heart receives O2 rich blood from lungs and pumps throughout the body to supply O2 and nutrients. The blood vessels that carry blood to and from the body tissues are called “systemic circuit” = systemic Left  CORONARY CIRCULATION release hormone The heart receives no nourishment from the blood as it passes through the (thyroid) chamber. Coronary arteries and its branches supply nutrition to the heart itself. R and L coronary arteries are the first branches of the ascending aorta R coronary artery supply blood to R atrium and back of both ventricles. Branches into marginal artery and others L coronary artery supply blood to L know the arteries atrium and L ventricle. Branches into circumflex artery and others  CORONARY CIRCULATION Major Coronary arteries Major Coronary Veins know this  CARDIAC MUSCLE CELLS Cardiac muscle cells are – short, fat, branched and interconnected. Like skeletal muscle , cardiac muscle is striated (less than skeletal) and contracts by “sliding filament theory”. Have thick and thin filament and Z, A, and I bands in sarcomere (like skeletal muscle) Each cardiac cell contains 1to 2 big nucleus. Large mitochondria accounts for 25-35% of cardiac cell vol.  CARDIAC MUSCLE CELLS Each cardiac cell (muscle fiber) is connected with next cell through “intercalated disc”. Each disc has many “desmosomes”( adherence structure between two cells) and “gap junctions” (plasma mem channel for communication pathway between cells). Desmosomes prevent adjacent cells to get separated during contraction and gap junction allow ions to pass from cell to cell, transmitting current across the entire heart. “Functional syncytium” -  Brachiocephalic artery Aorta Superior vena cava Pulmonary trunk Right atrium Left atrium Right ventricle Left ventricle Apex of the heart  Aorta Aortic semilunar valve Right atrium Left atrium Bicuspid valve Tricuspid valve Myocardium Chordae tendineae Right ventricle Loading… Trabeculae carneae Interventricular septum Left ventricle  Aorta Left atrium Aortic semilunar valve Bicuspid valve Tricuspid valve Chordae tendineae Right ventricle Left ventricle Interventricular septum Papillary muscles The Systemic Circulation > - Supplies blood to the brain , heart , and Gastrointestinal track