Tem cells are undifferentiated cells that have the ability to continue to grow and divide in their nonspecialized state for long periods of time (e. g., months or years).

although the genes found within stem cells are the same, stem cells differentiate into unique cell types (e. g., muscle cells, nerve cells, etc.) due to

a)mutations in their genetic code.
b)different patterns in their gene expression.
c)meiotic division and fertilization.
d)random segregation and proliferation.