Blood has three main functions: transport, protection and regulation. Blood transports the following substances: Gases, namely oxygen (O2) and carbon dioxide (CO2), between the lungs and rest of the body. Nutrients from the digestive tract and storage sites to the rest of the body.
Coronary arteries supply blood to the heart muscle. Like all other tissues in the body, the heart muscle needs oxygen-rich blood to function. Also, oxygen-depleted blood must be carried away
The chordae tendineae (tendinous chords), colloquially known as the heart strings, are cord-like tendons that connect the papillary muscles to the tricuspid valve and the bicuspid valve in the heart. Chordae tendineae are approximately 80% collagen, while the remaining 20% is made up of elastin and endothelial cells.