adapting to the body’s needs during various activities, and includes mechanisms for blood clotting and immune defense through white blood cells. Keywords circulatory system, heart, blood ...

There are three types of exercises that can be beneficial to our hearts, and they can be done by almost everyone without the ...

The heart is a pump, and the blood goes round, and round, and round all the time. And why does it do that? Why can't it just have a rest? Well, the blood has to be kept moving around all the time ...