Chapter Two Flashcards
Aortic semilunar valve
Valve located in the aorta that prevents the back flow of blood into the left ventricle
Aorta
The largest artery of the body, which transport blood from the left ventricle of the heart to the entire body
Atrioventricular (AV) node
Specialized cells that delayed the electrical conduction through the heart and allow the atria time to contract
Atrium
One of the upper two small chambers of the heart. The right atrium receives blood from the body through the vena cava and the left atrium receives blood from the lungs through the pulmonary vein
Automaticity
The ability of a cardiac cell to initiate an electrical impulse, without being stimulated by another source, causing a cardiac contraction
Bundle branches
Left and right branches of the bundle of His that conduct impulses down either side of that interventricular septum to the left and right ventricles
Bundle of His (AV bundle)
A bundle of fibers that originate in the AV node and enter the interventricular septum conducting electrical impulses to the left and right bundle branches
Cardiac cycle
The period of the beginning of one heartbeat to the beginning of the next; the cardiac cycle is made up of the systole and diastole
Conductivity
The ability of the heart cells to receive and transmit an electrical impulse
Contractility
The ability of the heart muscle cells to shorten in response to an electrical stimulus
Coronary circulation
The circulation of blood to and from the heart muscle
Deoxygenated blood
Blood the has little or minimal oxygen
Depolarization
The electrical activation of the cells of the heart that initiates contraction of the heart muscle
Diastole
The phase of the cardiac cycle when the heart is expanding and refilling; also known as the relaxation phase
Excitability
The ability of the heart muscle cells to respond to an impulse or stimulus
