summary of the book heartbeat by sharon creech
Heartbeat (novel) Twelve-year-old Annie is having a very significant year. Her mother is pregnant, her grandfather is forgetful, her best friend is always moody, and she has a new art assignment-draw an apple each day for one hundred days.
Cardiac cycle The cardiac cycle is the performance of the human heart from the beginning of one heartbeat to the beginning of the next. It consists of two periods: one during which the heart muscle relaxes and refills with blood, called diastole (die-ASS-toe-lee), followed by a period of robust contraction and pumping of blood, dubbed systole (SIS-toe-lee). After emptying, the heart immediately relaxes and expands to receive another influx of blood returning from the lungs and other systems of the bodyâ€”before again contracting to pump blood to the lungs and those systems. A normally performing heart must be fully expanded before it can efficiently pump again. Assuming a healthy heart and a typical rate of 70 to 75 beats per minute, each cardiac cycle, or heartbeat, takes about 0.8 second to complete the cycle.[1]