Circulatory System Quiz

The continuous movement of blood throughout the body, facilitated by the heart and blood vessels.

The system responsible for transporting blood, oxygen, carbon dioxide, and nutrients throughout the body. It consists of the heart, blood, and blood vessels.

The body's main fluid, containing red blood cells, white blood cells, platelets, and plasma. It's bright red in arteries and dark red in veins.

The fluid part of blood, composed primarily of water, proteins, salts, and other substances. It carries nutrients, hormones, and waste products.

A closed circulatory system means that blood always flows within blood vessels (arteries, veins, and capillaries). Open systems allow blood to flow outside of vessels.

Red blood cells are responsible for carrying oxygen from the lungs to the body's tissues and transporting carbon dioxide back to the lungs.

White blood cells are the body's defense system, protecting against infections by engulfing bacteria and other foreign invaders.

Platelets are small, cell-like fragments that help in blood clotting to prevent excessive blood loss at injury sites.

Thrombokinase, also known as thromboplastin, is an enzyme released from injured tissues and platelets that initiates the process of blood clotting.

This substance is converted from prothrombin (inactive) to thrombin (active) by the action of thrombokinase and calcium ions.