What is the lub-dub sound of a heartbeat? blood moving through the arteries and veins pacemaker controlling the heart rate atria contracting followed by the ventricles valves of the heart closing

What are the components of an effective weight-training program? a. conditioning, progression, generalization, overwork, balance, and recovery b. overload, progression, specificity, regularity, recovery, balance, and variety c. overwork, coordination, motivation, conditioning, regularity, and variety d. consistency, progression, rest, regression, balance, and specificity

What is the hormone in your brain that makes you feel happy?

10. what is one long-term effect of tobacco use? changes in brain chemistry coronary heart disease decreased appetite increased heart rate