The heart is a bag of muscle that squeezes itself about once every second, sending blood flowing throughout the body.
Your heart has 2 sides: left & right, separated by a thick, muscular wall. The heart contracts & relaxes, which means it is a ___________________. When your cardiac muscle contracts, it squeezes blood out of the heart through the arteries. When it relaxes, the veins fill youre your heart with more blood.
1.Hold your left hand in front of you, palm up. 2.Place first 3 fingertips of your right hand on the inside of your left wrist in the groove below the base of the thumb. 3.Use the timer/clock to count the number of times your heart beats in one minute. Record result in Science booklet. 4.Run in place for about one minute. 5.Repeat steps to take pulse again. 6.Record the results. 7.Explain what you observed in your booklet.