A computer-generated image of red blood cells. Nitric oxide—known by the formula NO—is so vital for humans’ internal physiological processes that it was crowned Molecule of the Year in 1992. It plays ...

Your sympathetic nervous system is one of the branches of your autonomic nervous system. It controls functions under unconscious control related to “fight or flight.” Your nervous system plays a ...

Having excess body weight can increase your blood pressure and affect your immune system. Learn what happens to blood ...

Your anatomy operates like a machine, it's success hinging on the work of over 70 organs, each with a unique function. From the heart's blood-pumping ability to the liver's filtering power, each ...

Renin-angiotensin system, or RAS, is a physiological mechanism essential to human body function. The SARS-CoV-2 virus causes overactivation and malfunction of this system. The RAS regulates innate ...