serotonin molecule structure, chemical formula

abstract art atom atomic background biochemistry biology brain cell cellular chain chemical chemicals chemistry clip clipart colorful compound concept design endorphin endorphine euphoria flat formula formulas graphic graphics happiness happy hormon hormone hormones icon icons illustration isolated logo logos medical medicine mind mindset model molecular molecule molecules nartoon neurotransmitter optimism positive research science scientific serotonin serotonins sign signs skeletal structural structure symbols transmitter vector web white