![]() ![]() Barnard stated he would "defer any suggestions as to a name" "until a later paper" but never got around to picking one from the numerous suggestions he received) or actively declined ( S. Traditionally, the discoverer enjoys the privilege of naming the new object however, some neglected to do so ( E. Historically the naming of moons did not always match the times of their discovery. Each object is listed in chronological order of its discovery (multiple dates occur when the moments of imaging, observation, and publication differ), identified through its various designations (including temporary and permanent schemes), and the discoverer(s) listed. In addition to use as a stimulant and flavoring agent, caffeine is included in many over-the-counter headache remedies.The timeline of discovery of Solar System planets and their natural satellites charts the progress of the discovery of new bodies over history.Caffeine intake has been demonstrated to reduce the risk of type II diabetes mellitus.While generally considered safe for people, caffeine can be very toxic to household pets, such as dogs, horses, or parrots. However, a tablespoon-sized amount of pure caffeine would be deadly. The lethal ingested dose for an adult person is estimated to be 13-19 grams. In other words, a person would need to drink between 50 and 100 cups of coffee to reach the lethal dose.Some people experience the symptoms of caffeine intoxication after ingesting as little as 250 mg per day. Too much caffeine can result in caffeine intoxication, which is characterized by nervousness, excitement, increased urination, insomnia, flushed face, cold hands/feet, intestinal complaints, and sometimes hallucinations. Tolerance causes the body to become sensitized to to adenosine, so withdrawal causes blood pressure to drop, which can result in a headache and other symptoms. However, continued exposure to caffeine leads to developing a tolerance to it. ![]() Its effects are short-lived and it tends not to negatively affect concentration or higher brain functions. Caffeine is quickly and completely removed from the brain.Caffeine also increases levels of the neurotransmitter dopamine. The stimulated nerve cells release the hormone epinephrine (adrenaline), which increases heart rate, blood pressure, and blood flow to muscles, decreases blood flow to the skin and organs, and causes the liver to release glucose. This reduces the ability of adenosine to bind to the receptors, which would slow down cellular activity. Caffeine is believed to aid wakefulness by blocking adenosine receptors in the brain and other organs.Black tea typically has more caffeine than oolong, green, or white tea. However, brewed coffee and steeped tea have approximately the same amount of caffeine. Tea leaves actually contain more caffeine per weight than coffee beans.Caffeine is generally consumed in coffee, cola, chocolate, and tea, although it is also available over-the-counter as a stimulant. However, more than half of all American adults consume more than 300 mg of caffeine every day, which makes it America's most popular drug. A normal dose of caffeine is generally considered to be 100 mg, which is roughly the amount found in a cup of coffee or tea.In humans, it stimulates the central nervous system, heart rate, and respiration, has psychotropic (mood altering) properties, and acts as a mild diuretic. Caffeine is also an addictive stimulant.It is added to colas and other soft drinks to impart a pleasing bitter note. When purified, caffeine is an intensely bitter white crystalline powder.Caffeine also limits germination of seeds near the plant that could grow to compete for resources. It paralyzes and kills insects that attempt to feed on the plants. In plants, caffeine acts as a natural pesticide.The molecule was first isolated by the German chemist Friedrich Ferdinand Runge in 1819.
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