Labels:bird | book | bulletin board | colostrum | person OCR: How OFTEN DOES OUR HEART BEAT? OUR HEART beats more than of a special type of muscle which once second every day of your never tires. This muscle contracts life As blood flows into your heart and relaxes 60 to 80 times minute: the muscles contract. and the blood during exercise the rate can increase flows out again. The heart is made to over 100 times a minute To HEAD To HEAD From HEAD To To LUNGS LUNGS From From LUNGS LUN G How your heart beats From BODY BODY 7OUR HEAI
