Immune System

(Shark Attack)

As blood is rushing out of the leg and into the water, the immune system tries to fend off foreign bacteria trying to enter the body through the open wound.

- User

Respiratory: Victim's going to be breathing hard so the oxygen will help white blood cells try and fight the bacteria coming inside the body.

Circulatory: Transports blood cells to try and replace blood that was lost.

Endocrine: Adrenaline is released because any sane person having their leg bitten off by a shark would be a little frightened and body would start shivering because they're scared and cold from being in the water.