A cell is the basic unit of life, and there are two main types of stem cells: embryonic and adult. Embryonic stem cells can become any type of tissue or organ, while adult stem cells are more limited. Scientists want to advance embryonic stem cell research for potential medical benefits, as these cells can renew themselves and adapt to their environment. However, this research is politically and ethically controversial. Former President Bush allowed only limited funding and Clinton revised related policies. Religions like Catholicism believe life begins at conception, while some Muslims permit research that benefits humanity if it does not question God. The document discusses these perspectives and debates regarding embryonic stem cell research.