Pine trees are all evergreens and possess needles as leaves and cones as part of their reproductive system. All pines are resinous Coniferous trees. Some Pine species grow as shrubs instead of trees.
How Fear Works. To produce the fight-or-flight response, the hypothalamus activates two systems: the sympathetic nervous system and the adrenal-cortical system. The sympathetic nervous system uses nerve pathways to initiate reactions in the body, and the adrenal-cortical system uses the bloodstream. The combined effects of these two systems are the fight-or-flight response. When the hypothalamus tells the sympathetic nervous system to kick into gear, the overall effect is that the body speeds up, tenses up and becomes generally very alert. If there's a burglar at the door, you're going to have to take action -- and fast.
Adrenaline What It Is: Commonly known as the fight or flight hormone, it is produced by the adrenal glands after receiving a message from the brain that a stressful situation has presented itself. What It Does: Adrenaline, along with norepinephrine (more on that below), is largely responsible for the immediate reactions we feel when stressed. Imagine you're trying to change lanes in your car, says Amit Sood, M.D., director of research at the Complementary and Integrative Medicine and chair of Mayo Mind Body Initiative at Mayo Clinic.