circulatory system

To transport blood, nutrients, and gases throughout the body.

Respiratory system.

It pumps blood first to the lungs, back to the heart, and then around the rest of the body.

Oxygen.

Red blood cells, white blood cells, plasma, and platelets.

They carry oxygen from the lungs to the body's tissues and transport carbon dioxide back to the lungs.

To ensure blood flows in one direction through the heart.

The aorta.

Arteries carry blood away from the heart, while veins carry blood back to the heart.

They allow for the exchange of oxygen, carbon dioxide, nutrients, and waste between blood and tissues.