Answer to Question 1
Stem cells are capable of dividing and renewing themselves for long periods, they are unspecialized, and they can give rise to specialized cell types. Research on stem cells is advancing knowledge about how an organism develops from a single cell and how healthy cells replace damaged cells in an adult organism. This promising area of science is also leading scientists to investigate the possibility of cell-based therapies to treat disease, which is often referred to as regenerative or reparative medicine.
Answer to Question 2
tracheostomy