Use a description of C. elegans development to distinguish clearly between differentiation and determination

Question

What will be an ideal response?

Answer 1

The developmental potential of a cell describes the range of different cell types it has the potential to become. As development progresses, the potential of individual cells decreases until, ultimately, their genetic fate is determined. Thus, determination implies a stable change at the level of gene expression that means a cell is committed to a certain developmental fate. Differentiation is the process that follows determination in which the cell develops its cell-specific expression profile. Differentiation results in distinct cell types with clearly identifiable functions, such as a muscle or nerve cell.
The C. elegans example from the text involved vulva formation. The vulva forms during the last larval stage from six precursor cells, called vulval precursor cells (VPCs). Three of these larval
cells give rise to structures of the vulva itself, the 1° cell and two 2° cells of the vulva. The other three differentiate into hypodermis (3° cells). Initially, each of the six VPCs has the potential to differentiate along any of the pathways–1°, 2°, or 3°. If the anchor cell is destroyed, no vulva will form because all six VPCs differentiate with a 3° fate and become hypodermis. Thus, these six cells are determinate, while the anchor cell must be present to induce VPCs to differentiate with 1° or 2° fates and thus form the vulva. Because all the VPCs are capable of the same kinds of differentiation, they are said to form an equivalence group.