Quick Answer. Swedish chemist and philanthropist Alfred Bernhard Nobel invented dynamite. Nobel mixed nitroglycerine and kieslguhr (diatomaceous earth) in a series of experiments in the 1860s to create the explosive, according to History Today. Nobelâs work in the arms industry led him to establish the Nobel prize.
Your bones and muscles work together through a series of impulses and signals communicated between the brain and skeletal muscles. In order to move, the nervous system signals a skeletal muscle to contract. When the muscle contracts, this movement causes the attached bone (or bones) to follow.
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.