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 　　Taste may be the least understood of our five senses, even basic questions like where the taste bugs¹ come from remain mysterious until now. In the study published in the journal Stem Cell, scientists identified the lose of parental² cell that gives rise to the daughter cell responsible for taste. Taste bugs are made of lusters³ of taste cells, which contain the receptors for sweet, salty, sour, bitter, and umami. The are concentrated in the bumpy⁴ papillae that covered the tongue surface. But taste bugs are not static *. The resident taste cells live only about too weeks before being replaced by new born baby taste cells. After all the bits * now permanent. But no one knew the address of taste cell nursery. To track it down, scientists scanned the tongue for cell that produced the same marker protein as the body's other stem cells, which give rise to our other specialized⁵ cells. The researchers discovered the reservoir of stem cells that lie in the trenches⁶ around the papillae at the back of the tongue. This stem cells can produce all of the different taste cell types and so allow us to savor⁷ all of life's flavors.