From iiknowledge.com:

Stem cells are cells with the unique potential to become multiple different types of cell within the body. Most of your cells are equipped to accomplish a specific job, whether carrying oxygen in your blood or transmitting messages to and from your brain. These specialists are known as differentiated cells.

Stem cells, on the other hand, have the flexibility to specialize into a variety of cell types. And unlike most differentiated cells, they can replicate many times, giving rise to both more stem cells and to specialized cells.

When it comes to researching stern cells and the therapies that rely on them, getting hold of these cells is a major obstacle. ESCs are taken from donated embryos from IVF procedures,but this stirs up thorny ethical issues.

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