21.   Ramachandran suspects that there are specialized cells in their brains that can recognize particular patterns and then tell the skin what pigment bodies to expand or contract.

22.   Secreted by specialized cells in the stomach and the upper part of the small intestine, ghrelin acts on the brain.

23.   Snyder said that his experiment showed, in principle, that neural stem cells can migrate all over the brain and develop into the right kinds of specialized cells.

24.   Specialized cells grow into perfectly designed organs, which join up with other organs.

25.   Stem cells can both renew themselves and generate the more specialized cell types of the organ to which they belong.

26.   Such cells apparently have the potential to develop into most of the specialized cells and tissues of the body, including muscle cells, nerve cells and blood cells.

27.   Stem cells produce other types of specialized cells.

28.   The blood-brain barrier consists of specialized cells that line the capillaries within the brain.

29.   The company hopes to use the procedure, which has never been done on humans, to create specialized cells for new medical treatments.

30.   The company says it later added a jellyfish gene to the hybrid in a first step toward learning how to guide the development of stem cells into specialized cells.