01 / Location & anatomical relationships
Inside the heart and blood vessels throughout your body.
02 / Structure & organization
Plasma carries dissolved substances, while red cells, white cells and platelets provide specialized functions. Hemoglobin in red cells binds oxygen. Platelets and coagulation proteins cooperate to form a hemostatic response when vessels are damaged.
03 / Function
It also carries cells that fight infection and help stop bleeding.
04 / Mechanism
Plasma is the liquid carrying dissolved substances and cells. Red blood cells transport oxygen using hemoglobin, white blood cells help defend the body, and platelets help form clots. Blood also distributes heat as it circulates.
Working together: circulatory system
Your heart pumps blood to your lungs to collect oxygen. Blood then delivers oxygen to body cells and carries carbon dioxide back to your lungs.
Meet this body system →FOR DEEPER STUDY
Connect structure with function
Blood is a connective tissue with a liquid extracellular component. Oxygen transport, immune defense and clotting involve distinct components rather than one interchangeable cell type.
Check your understanding
Locate the blood in relation to its neighbors. Explain how the structural features described above support its function, then distinguish it from a nearby structure with a different role.
Keep learning
Further reading: NHLBI: How the Heart Works.
Continue with OpenStax Anatomy and Physiology for system-level study. This atlas is educational and has not undergone independent medical peer review.