Human Heart Anatomy Quiz PDF

Location of the Human Heart: ​ The human heart is located within the thoracic cavity, between the lungs in the space known as the mediastinum Pulmonary Circulation: ​ The circulation of blood to the lungs: Deoxygenated blood leaves the heart and travels to the lungs where it is oxygenat...

Location of the Human Heart: ​ The human heart is located within the thoracic cavity, between the lungs in the space known as the mediastinum Pulmonary Circulation: ​ The circulation of blood to the lungs: Deoxygenated blood leaves the heart and travels to the lungs where it is oxygenated and returned to the heart. -​ Blood leaves the Pulmonary Valve into the pulmonary trunk. It is distributed by the right and left pulmonary arteries to the lungs, where it unloads CO2 and loads O2. Blood returns to the heart via pulmonary Veins to the left Atrium. Systemic Circulation: ​ The blood circulation to the body: Oxygenated Blood leaves the heart and travels throughout the body, delivering oxygenated blood and returning to the heart. -​ Contraction of the left ventricle forces the Aortic valve to open blood flows through the aortic valve into the ascending aorta where it is distributed to the body, blood returns to the right atrium via the vena cava Layers of the Heart Wall: -​ Pericardial Sac -​ Epicardium -​ Myocardium -​ Endocardium Function of the Pericardial Sac: ​ Protects the heart, lubrication it, and maintains its position (protects from infection) Function of the Epicardium: ​ Protects the heart, producing factors that help the cardiac cells properly develop and ensures proper response to cardiac cell injury Function of the Myocardium: ​ Responsible for the contractile function of the cardiac pump (contracts and relaxes the heart walls) The function of the Endocardium: ​ Directing blood through the heart and regulating the heartbeat Major External Anatomical Features of the Heart: -​ Aortic Arch -​ Superior and Inferior vena cava -​ Branches of Right Pulmonary Artery -​ Left and right Pulmonary Veins -​ Left and right Auricles  -​ Right and Left Atriums -​ Left and Right Ventricles -​ Coronary sulcus -​ Ligamentum arteriosum -​ Ascending Aorta -​ Pulmonary trunk -​ Anterior interventricular Sulcus -​ Apex of Heart -​ Coronary Sinus -​ Fat -​ Posterior Interventricular Sulcus -​ Pericardium Major Internal Anatomical Features of the Heart: -​ interatrial Septum -​ Fossa Ovails -​ Pectinate muscles -​ Left and Right AV valves -​ Tendinous cords -​ Trabeculae Carneae -​ Pulmonary Valve -​ Papillary Muscle -​ Interventricular septum -​ Endocardium -​ Myocardium -​ Epicardium Functions of the External Anatomical Features: -​ Pericardium: The fibrous pericardium is made of tough, dense connective tissue that protects the heart and maintains its position in the thorax -​ Auricles: Auricles are relatively thin-walled structures that can fill with blood and empty into the atria or upper chambers of the heart -​ Sulci: major coronary blood vessels are located in these sulci. Functions of the Internal Anatomical Features: -​ Epicardium: The outermost layer of the wall of the heart is also the innermost layer of the pericardium, the epicardium, or the visceral pericardium described above. -​ Myocardium: Contraction of the myocardium pumps blood through the heart, into the major arteries, and out into circulation. -​ Endocardium: The endocardium lines the chambers where the blood circulates and covers the heart valves.  -​ Chambers: the right atrium (plural = atria) and the left atrium, acts as a receiving chamber and contracts to push blood into the lower chambers, the right ventricle and the left ventricle. The ventricles serve as the primary pumping chambers of the heart, propelling blood to the lungs (the pulmonary circuit) or to the rest of the body (the systemic circuit). -​ Valves: In order to ensure unidirectional flow of blood through the heart, specialized structures called valves are found between the chambers and circuits. Trace the Pathway of Blood through the Heart: -​ Blood enters the heart through the superior and inferior vena cava into the right atrium, then flows through the tricuspid valve to the right ventricle, is pumped through the pulmonary valve into the pulmonary artery to the lungs, returns to the heart via the pulmonary veins into the left atrium, passes through the mitral valve to the left ventricle, and finally exits the heart through the aortic valve into the aorta, distributing oxygenated blood throughout the body. Trace the pathway of Blood through the Pulmonary Circuits: ​ Leaves the Pulmonary Valve into the pulmonary trunk, blood is distributed by right and left pulmonary arteries to the lungs, unloads CO2 and loads O2. Blood returns to the heart via pulmonary Veins to the left Atrium. Trace the pathway of Blood through the Systemic Circuits: ​ The systemic circuit transports oxygenated blood to virtually all of the tissues of the body and returns relatively de-oxygenated blood and carbon dioxide to the heart to be sent back to the pulmonary circulation -​ Contraction of the left ventricle forces the Aortic valve to open blood flows through the aortic valve into the ascending aorta where it is distributed to the body, unloads O2, and loads CO2, Deoxygenated blood returns to the right atrium via the vena cava. Label the Major events in an ECG Trace: ​ Def: The combined electrical activity of the different myocardial cells produces electrical currents that spread through the body fluids. These currents are large enough to be detected by recording electrodes placed on the surface skin: -​ P Wave: produced by arterial depolarization -​ QRS Complex: Produced by ventricular depolarization; atrial repolarization also occurs during this time -​ T Wave: produced by ventricular repolarization Explain the Electrical Event happening at Each: ​ Atrial Depolarization: the electrical excitation of the atria (upper chambers of the heart), which essentially means the wave of electrical signal that causes the atria to contract Ventricular Depolarization: the electrical activation of the heart's ventricles Ventricular Repolarization: consisting of a recovery period with the return of the ions to their previous resting state, which corresponds with the relaxation of the myocardial muscle, thus setting the stage for the next depolarization and contraction. Explain the Mechanical Event happening at Each -​ Atrial Systole: The atria contract which decreases the volume of the chamber and increases pressure on the blood found in these chambers. This forces blood from the atria, through the atrioventricular valves into the ventricles -​ Early Ventricular Systole: The increase in pressure due to ventricular contraction forces the AV valves to close which prevents the backflow of blood. Semilunar valves remain closed because ventricular pressure is lower than pressure in major blood vessels -​ Later in the Ventricular Systole: Atria is still relaxed while ventricles continue to contract, AV valves remain closed, but once ventricular pressure exceeds pressure in the major blood vessels the semilunar valves are forced open. Blood is ejected into the aorta and pulmonary trunk. -​ Early ventricular Diastole: Atria and Ventricles are relaxed. Once the pressure in the aorta and pulmonary arteries exceeds the pressure in the ventricles the semilunar valves close. Atria fills with blood again and AV valves are closed -​ Early to mid-ventricular diastole: atria and ventricles are relaxed. Ventricular pressure is now below atrial pressure and aortic/pulmonary trunk pressure. Semilunar is closed, AV valves open, and blood flows from the atria into ventricles, ventricles rapidly fill with blood