Question

how does nutrition takes place in a bud of hydra

Answer 1

when there is plenty of food in the hydra it forms buds by reproducing asexually then,when the buds have become matured enough to survive on their own and provide their own nutrition , they get separated from each other.....

Answer 2

Daniel Martinez claimed in a 1998 article in Experimental Gerontology that Hydra are biologically immortal.[11] This publication has been widely cited as evidence that Hydra do not senesce (do not age), and that they are proof of the existence of non-senescing organisms generally. In 2010 Preston Esteppublished (also in Experimental Gerontology) a letter to the editor arguing that the Martinez data refute the hypothesis that Hydra do not senesce.[12]

The controversial unlimited life span of Hydrahas attracted the attention of natural scientists for a long time. Research today appears to confirm Martinez' study.[13] Hydrastem cells have a capacity for indefinite self-renewal. The transcription factor, 
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