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The cells in your taste buds are replaced all the time: studies in rats and mice put their average life at about 8 to 12 days. Different kinds of taste cell last for different lengths of time.

Human biology

Health

The story behind the card

Adults have roughly 2,000 to 8,000 taste buds, mostly on the small bumps of the tongue, with others on the palate and in the throat. Each bud is a cluster of about 50 to 100 cells, supplied with new cells made in the surrounding lining. The first estimate came in 1965, when Lloyd Beidler and Robert Smallman tracked labelled cells in rats and found an average life of about ten days. A 2013 study in mice showed that the types differ. Cells that detect sweet, bitter and savoury (umami) tastes were replaced fastest, half of them within about 8 days, while cells that respond to sour lasted longer, with half gone only after about 22 days. The popular “tongue map” is a myth: every part of the tongue with taste buds can sense all the basic tastes.

Türkçe oku
Tat tomurcuklarınızdaki hücreler sürekli yenilenir: Sıçan ve farelerde yapılan çalışmalara göre bu hücreler ortalama 8 ila 12 gün yaşar. Farklı tat hücresi türlerinin ömrü ise birbirinden farklıdır.

Yetişkinlerde kabaca 2.000 ile 8.000 arasında tat tomurcuğu bulunur; çoğu dildeki küçük kabarcıkların üzerindedir, bir kısmı da damakta ve boğazdadır. Her tomurcuk 50-100 kadar hücreden oluşan bir kümedir; eskiyen hücrelerin yerini çevredeki dokuda üretilen yeni hücreler alır. İlk tahmin 1965'te geldi: Lloyd Beidler ile Robert Smallman sıçanlarda işaretledikleri hücreleri izledi ve ortalama ömrü yaklaşık on gün buldu. 2013'te farelerle yapılan bir çalışma, hücre türlerinin farklı sürelerde yenilendiğini gösterdi. Tatlı, acı ve umami (et suyu tadı) algılayan hücreler en hızlı yenilenenlerdi: Yaklaşık 8 günde yarısı yerini yenilerine bırakıyordu. Ekşiye tepki veren hücrelerde ise bu süre yaklaşık 22 gündü. Yaygın “dil haritası” da bir efsanedir: Dilin tat tomurcuğu bulunan her bölgesi temel tatların hepsini algılayabilir.

Sources and further reading

Background reading: Taste bud
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