What is the main function of this organ system It protects vital organs from injury. It is the first line of defense and keeps the body warm. It transports nutrients and oxygen to body cells. It produces hormones that regulates growth and metabolism.

Organ systems & their main functions

Explanation:

The chest bones Rib Cage & spine - protects the vital organs (heart, lung,liver) from injury & provides structural support for body.

Skin is the body's first line of defense & keeps the body warm. In case of any invading infection, fever - body temperature rise fights it.

Circulatory system (containing heart) & its body fluid blood -  transports nutrients and oxygen to body cells

Endocrine system regulates growth, produces hormones - that target organs via bloodstream.

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