The cardiac chambers consist of two atria. two ventricles. and four valves The cardiac valves consist of thin flaps of tough, flexible, endothelium-covered fibrous art tissue firmly attached at the Pul base to the fibrous valve rings Movements of the valve leaflets are essentially passive, and the orientation of the cardiac valves is responsible for the unidirectional flow of blood through the heart
The cardiac chambers consist of two atria, two ventricles, and four valves The cardiac valves consist of thin flaps of tough, flexible, endothelium-covered fibrous tissue firmly attached at the base to the fibrous valve rings. Movements of the valve leaflets are essentially passive, and the orientation of the cardiac valves is responsible for the unidirectional flow of blood through the heart
Cardiac valves are interposed between atria and ventricle Atrioventricular valves The tricuspid valve lies between the right atrium and right ventricle and is se made up of three cusps, The mitral valve lies between the left atrium and left ventricular and has two cusps
The tricuspid valve lies between the right atrium and right ventricle and is made up of three cusps, Cardiac valves are interposed between atria and ventricle • Atrioventricular valves . The mitral valve lies between the left atrium and left ventricular and has two cusps
Semilunar valves The valves between the right and between the left ventricle ventricle and pulmonary arter and aorta consist of three cuplike ly cusps attached to the valve rings. PU At the end of the reduced ejection phase of ventricular systole, blood flow reverses briefly toward the ventricles. This flow reversal snaps the cusps together and prevents regurgitation of blood into the ventricles
The valves between the right ventricle and pulmonary artery and between the left ventricle and aorta consist of three cuplike cusps attached to the valve rings. • Semilunar valves At the end of the reduced ejection phase of ventricular systole, blood flow reverses briefly toward the ventricles. This flow reversal snaps the cusps together and prevents regurgitation of blood into the ventricles
The pericardium is an epithelialized fibrous sac that invests the heart The pericardium consists of a visceral laver that is adherent to the epicardium and a parietal layer separated from the visceral layer by a thin layer of fluid. The fluid layer provides lubrication for the continuous movement of the enclosed heart. The pericardium is nor very distensible and thus strongly resists a large, rapid increase in cardiac size. Therefore the pericardium helps prevent sudden over distention of the heart chambers
The pericardium consists of a visceral layer that is adherent to the epicardium and a parietal layer separated from the visceral layer by a thin layer of fluid. The fluid layer provides lubrication for the continuous movement of the enclosed heart. The pericardium is nor very distensible and thus strongly resists a large, rapid increase in cardiac size. Therefore the pericardium helps prevent sudden over distention of the heart chambers. The pericardium is an epithelialized fibrous sac that invests the heart
The Cardiac Cycle is the Sequential Contraction and Relaxation of atria and ventricles Ventricular systole is initiated by 13 Ventricular excitation ontic valve closes Aortic (1)Isovolumic contraction pressure The interval between the start of Mitral ventricular systole and the opening of the semilunar valves is called isovolumic eft atrial pressu contraction because ventricular volume isi,A constant during this brief period. Ventricular pressure rises abruptly 220
The Cardiac Cycle is the Sequential Contraction and Relaxation of Atria and Ventricles (1) lsovolumic contraction Ventricular systole is initiated by Ventricular excitation • The interval between the start of ventricular systole and the opening of the semilunar valves is called isovolumic contraction because ventricular volume is constant during this brief period. • Ventricular pressure rises abruptly