One cardiac cycle is .8 seconds. A complete heartbeat is produced in one cardiac cycle. <span>The period of time that begins with contraction of the atria and ends with ventricular relaxation is known as the cardiac cycle. The period of contraction that the heart undergoes while it pumps blood into circulation is called systole.</span>
Answer: In addition to slowing the overall expansion, gravity causes local clumping of matter into stars and galaxies. ... Within the Local Group, the gravitational interactions have changed the inertial patterns of objects such that there is no cosmological expansion taking place.
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