HOW THE HEART BEATS
The heart acts in two main phases. In the first phase
the atria fill with blood. The atria contract
The heart works in a regular rhythm. A group of cells found in the right atrium
called the pacemaker or sinoatrial (SA) node
Pulse
The heart pulses about 70 times each minute. If you touch the inside of your wrist just below your thumb
you can feel a pulse in the artery in your wrist rise and fall. This pulse is the alternating expansion and relaxation of the artery wall caused by contraction of the left ventricle. The number of times the artery pulses is the number of times your heart beats.
Blood pressure
Blood pressure is a measure of how much pressure is exerted against the vessel walls by the blood. Blood-pressure readings can provide information about the condition of arteries. The contraction of the heart
or systole (SIS tuh lee)
HOW THE HEART BEATS
The heart acts in two main phases. In the first phase
the atria fill with blood. The atria contract
The heart works in a regular rhythm. A group of cells found in the right atrium
called the pacemaker or sinoatrial (SA) node
Pulse
The heart pulses about 70 times each minute. If you touch the inside of your wrist just below your thumb
you can feel a pulse in the artery in your wrist rise and fall. This pulse is the alternating expansion and relaxation of the artery wall caused by contraction of the left ventricle. The number of times the artery pulses is the number of times your heart beats.
Blood pressure
Blood pressure is a measure of how much pressure is exerted against the vessel walls by the blood. Blood-pressure readings can provide information about the condition of arteries. The contraction of the heart
or systole (SIS tuh lee)
