This book explains how the body's circulatory and respiratory systems work and shows how they are essential for life. We take a close look at how we breathe and speak, how the heart beats, and how blood works. We will also consider problems that can occur with the heart and lungs and what can be done to keep them healthy.
This book explains how the body's circulatory and respiratory systems work and shows how they are essential for life. We take a close look at how we breathe and speak, how the heart beats, and how blood works. We will also consider problems that can occu