Lab Quiz Heart
Structure from which chordae tendinae originate
Prevents blood movement from right ventricle to right atrium
Membranes around the heart
Prevents blood movement from the left ventricle to left atrium
Gives rise to left and right pulmonary arteries
Drains blood from myocardium into the right atrium
Inner lining of heart chamber
Layer largely composed of cardiac muscle tissue
Space containing serous fluid to reduce friction during heartbeats
Drains blood from myocardial capillaries
Supplies blood to heart muscle
Distributes blood to body organs except the lungs
Depolarization of atrial fibers
P-Q (P-R) Interval
Time for cardiac impulses from SA node through AV node
Depolarization of ventricular fibers
Time for ventricles to contract
Time from ventricular depolarization to end of ventricular repolarization
Repolarization of ventricular fibers
About what percentage of blood passes into the ventricles before the atrial walls contract?
What is the period during which a heart chamber is contracting called?
What is the period during which a heart chamber is relaxing called?
During ventricular contraction
When are the AV valves (tricuspid and mitral valves) closed?
During ventricular relaxation
When are the AV valves open?
When the pressure in the ventricles exceeds the pressure in the pulmonary trunk and aorta.
When do the pulmonary and arotic valves open?
Vibrations in heart tissues created by changes in blood flow.
What causes heart sounds?
When the AV valves are closing.
When does the first sound of a cardiac cycle occur?
When the semilunar valves are closing.
When does the 2nd sound of a cardiac cycle occur?
What is the sound called when blood leaks back through an incompletely closed valve?
Specialized Cardiac Muscle Tissue
What are the fibers of the cardiac conduction system called?
The SA node (Sinoatrial node)
Under normal circumstances, what serves are the pacemaker of the heart?
in the inferior portion of the interatrial septum
Where is the AV (atrio ventricular) node located?
The AV bundle
What do the large fibers on the distal side of the AV node makeup?
What are the fibers that carry cardiac impulses from the interventricular septum into the myocardium called?
What is a recording of electrical changes occuring in the myocardium during the cardic cycle called?
Between cardiac cycles, cardiac muscle fibers remain __?__ with no detectable electrical changes.
The P wave
What wave corresponds to depolarization of the muscle fibers of the atria?
The QRS complex corresponds to de-polarization of the muscle fibers in the__?__.
The T wave corresponds to repolarization of the muscle fibers in the ___?___.
Atrial repolarization occurs at the same time as ventricular depolarization. The QRS complex hides atrial repolarization.
Why is atrial repolarization not observed in an ECG?
What is a rapid heart beat called?
What is a slow heart beat called?
What distributes blood to body organs (systemic circuit) except lungs?
What drains blood from myocardial capillaries?
What supplies blood to heart muscle?
What drains blood from myocardium into the right atrium?
What is the inner lining of the heart chamber called?
The mitral valve A.K.A. bicuspid valves
What prevents blood movement from the right ventricle to the right atrium?
What is the layer largely composed of cardiac muscle tissue?
The papillary Muscle
What is the structure from which the Cordae Tendineae originate?
What is the space called that contains serous fluid that reduces friction during heartbeats?
What are the membranes around the heart called?
The pulmonary trunk
What structure gives rise to the left and right pulmonary arteries?
Tricuspid valve a.k.a. right atrioventricular valves
What prevents blood movement from right ventricle to right atrium?