Description Explore the essential functions of the human heart with this comprehensive multiple-choice worksheet designed for middle and high school students. This resource contains 100 detailed, non-repeating questions focused on how the heart supports life through circulation, oxygen delivery, waste removal, and physiological adaptations during exercise, stress, sleep, and illness. Students will examine the roles of atria, ventricles, valves, coronary arteries, and the sinoatrial node while u