The adrenaline hormone is secreted by adrenal gland, a gland present on top of the kidney. During emergency situations like anger, danger and stress etc., this hormone prepares our body to function at maximum efficiency. It increases blood flow into muscles, breathing and heart rate and causes liver to put more stored glucose into our blood which causes production of high energy. Thus, if adrenaline is secreted in large amounts then it prepares our body for action.