Question

hi, I have a simple science question: How do you know that a cell is 'specialised'?

Answer 1

anyone? :(

Answer 2

A cell is defined as specialized when it reaches its typical shape and starts its own methabolism. plant cells build a thick wall and acquire a peculiar shape depending on their function. Animal cells also acquire typical shape (just think about the diversity between a neuronal cell and an epithelium). in both cases cells stop dividing. in the organisms stem or meristematic cells keep dividing. they are the non-differentiated cells in animals and plants respectively. specialized cells posses specific gene-activation or inactivation programmes so that, for example, neuronal cells produce ion-channels whereas bones produce none. on the contrary, bone cells produce other proteins not found in neuronal cells. non-differentiated cells usually activate genes useful for rapid synthesis of DNA and dividing, or at least proteins for "basic" cell functions. muscle cells don't divide but they build a looooot of structural proteins useful for contraction. keep also in mind that the term "differentiated cell" only has sense when speaking of multicellular organisms