Where does cell differentiation occur?

Between the eighth and sixteenth weeks of pregnancy, the human fetal pituitary gland undergoes cellular differentiation. Researchers detected a small quantity of pituitary growth hormone as early as the ninth week of gestation. This hormone then significantly rises between the eleventh and sixteenth weeks. During this period, there's a rapid development of the pituitary acidophilic cells. In simpler terms, in the middle stages of pregnancy, the baby's pituitary gland goes through significant changes as specific cells begin producing and releasing growth hormone, crucial for the development and differentiation of certain pituitary cells.

In addition to this, cell differentiation happens wherever stem cells exist like in adult stem cells located in tissues such as red bone marrow and skin. Cell differentiation also occurs during metamorphosis of larval form and after the separation of parts in asexual reproduction. It is a process which continues throughout an individual's lifespan continuously.