In 1913 Bohr proposed his quantized shell model of the atom to explain how electrons can have stable orbits around the nucleus.n 1913 Bohr proposed his quantized shell model of the atom to explain how electrons can have stable orbits around the nucleus.
Norepinephrine, also called noradrenaline, is an organic chemical in the catecholamine family that functions in the human brain and body as a hormone and neurotransmitter.n the most basic terms, the function of norepinephrine is to mobilize the brain and body for action. Norepinephrine release is lowest during sleep, rises during wakefulness, and reaches much higher levels during situations of stress or danger, in what has been called the fight-or-flight response.
Norepinephrine is both a hormone and a neurotransmitter. As a hormone, secreted by the adrenal gland, it works alongside adrenaline (also known as epinephrine) to give the body sudden energy in times of stress, known as the fight or flight response.