Cardiovascular system reading 4 Flashcards
What forces the movement of blood through the heart chambers and into the vessels?
Pressure changes
Where is blood moving during the period of ejection?
Ventricles to great vessels
The sequence of events that begins with heart muscle contraction and ends with the beginning of the next contraction is called the what?
cardiac cycle
AV valves are open when ______.
ventricles are relaxed
The phase of the cardiac cycle during which the ventricles are contracting, but all valves remained closed is called ______.
isovolumetric contraction
The __ is a repeating series of contraction and relaxation events that move blood through the heart.
cardiac cycle
The duration of the cardiac cycle is shortest ______.
in a new-born
The phase of the cardiac cycle during which the ventricles are contracting, but ventricular pressure has not yet exceeded arterial pressure is called ______.
isovolumetric contraction
The normal duration of one cardiac cycle in a healthy adult is slightly less than one ______.
second
Ejection of blood from the ventricles occurs when ______ pressure exceeds ______ pressure.
ventricular, atrial
True or false: The duration of the cardiac cycle remains the same throughout one’s life.
False
The normal cardiac cycle in an adult is _____ seconds.
0.7 - 0.8
In ventricular ejection, a higher pressure is required to open the _____ semilunar valve than to open the _____ semilunar valve.
aortic, pulmonary
The closing of the semilunar valves occurs at the beginning of the ______ phase of the cardiac cycle.
isovolumetric relaxation
Most of the blood enters the ventricles from the atria by ______ processes.
passive
The importance of atrial contraction increases during ______.
exercise
During exercise, the heart rate will increase, which means there is ______ time for passive ventricular filling and a need for ______ atrial contraction.
less, more
The lowest volume in the ventricles during the cardiac cycle would be the ______.
end-systolic volume
Identify the events that occur during ventricular systole.
Ventricles contract.
Blood moves from ventricles through semilunar valves.
The lowest volume in the ventricles during the cardiac cycle would be the ______.
end-systolic volume
Identify the events that occur during ventricular diastole.
Ventricular filling
Isovolumetric relaxation
The time between the second heart sound and the next first heart sound represents ______.
ventricular diastole
When blood pressure is measured in the brachial artery, it reflects blood pressure in the ______.
aorta
The heart sounds heard through a stethoscope are the result of ______.
closing of the valves
Why is the dicrotic notch seen on the aortic pressure curve?
The pressure in the aorta rises slightly after the aortic valve closes.
The third heart sound is produced by ______.
turbulent blood flow
