Caffeine, noun: An alkaloid and an important component of coffee as well as tea, guarana and cacao. It has a stimulating effect and increases one’s ability to concentrate. Note: In the journal “Science,” researchers report that the concentration of caffeine in the nectar of some varieties of coffee, those that correspond to a cup of instant coffee, doesn’t seem to bother bees in small doses, but rather gives them a helping hand. In the (bee) group that contained caffeine, three times as many bees still remembered the fragrance learned after a day. After three days, it was still twice as many bees.