The term stem cell was first used in the 19th century to describe the Darwin-esque evolution of multicellular organisms over millions of years. Today the term is used to reflect the evolutionary-like moulding that transforms a naïve cell into a mature committed specialist in a matter of days. Stem cells respond to chemical signals in their immediate environment prompting them to mature or differentiate, into specialised cells across our bodies. Organs can avail of part-mature stem cells locally to repair damaged tissue. This ball of neural stem cells (a neurosphere, with its DNA stained blue) has received the chemical cue to differentiate into neurons. After 45 days, the newly-transformed neurons (stained red) branch out in all directions. One day soon stem cell therapy could help reverse the damage done by Parkinson’s or Alzheimer’s.
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BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
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