The heart is the body's hardest-working muscle. Whether you're awake or asleep, or exercising or resting, your heart is always at work. It pumps blood through arteries to deliver oxygen to organs and ...

Your heart is one of the most important organs of the body. It pumps oxygenated blood to the body, helps in nutrient delivery in the body, sends oxygen-poor blood to the lungs, receives oxygen-rich ...

Hierarchical structure of muscle and activation of thin filaments. In both skeletal and cardiac muscles under a relaxed state, a low intracellular calcium ion concentration is maintained and the ...