Cell differentiation
When a cell differentiates, it gains specific sub-cellular structures that enable it to perform a particular function. This transformation turns a generic cell into a specialised cell that serves a distinct purpose in the body. Think of it as cells choosing their career paths!
Cell differentiation is crucial for development because it allows organisms to form diverse tissues and organs. As an embryo grows, cells must take on different roles to create everything from skin to nerves to muscle. Without this process, we'd just be blobs of identical cells!
In animals, most cell differentiation happens during early embryonic development. Once an animal matures, cell division becomes mainly limited to repair and replacement (like producing new blood or skin cells). Plants work differently - many of their cells retain the ability to differentiate throughout their entire lifespan.
Interesting fact: Not all cells in adult bodies are differentiated! Stem cells found in places like bone marrow remain undifferentiated. These cellular "blank slates" can transform into different cell types as needed, which is why they're so valuable in medicine.