The term that describes processes by which cells with identical genotypes become structurally and functionally distinct from one another is cell differentiation.

Here's why:

* Genotype: The genetic makeup of an organism.

* Identical Genotype: All cells in a multicellular organism originate from a single fertilized egg and therefore share the same genetic blueprint.

* Structural and Functional Distinctiveness: Cells in different tissues and organs have specialized structures and functions (e.g., muscle cells contract, nerve cells transmit signals, epithelial cells form protective layers).

Cell differentiation is the process by which these differences arise. It's controlled by a complex interplay of:

* Gene expression: Different genes are activated or repressed in different cell types, leading to the production of specific proteins.

* Environmental factors: Signals from neighboring cells, the extracellular matrix, and other environmental cues can influence cell differentiation.

So, while all cells in an organism share the same genetic information, cell differentiation allows them to become diverse and specialized, enabling the formation of complex tissues and organs.