What are the benefits and disadvantages of determinate and indeterminate cell differentiation, and w

The determination of a cell to a particular fate can be broken down into two states where the cell can be specified (committed) or determined. In the state of being committed or specified, the cell type is not yet determined and any bias the cell has toward a certain fate can be reversed or transformed to another fate. If a cell is in a determined state, the cell’s fate cannot be reversed or transformed. In general, this means that a cell determined to differentiate into a brain cell cannot be transformed into a skin cell. Determination is followed by differentiation, the actual changes in biochemistry, structure, and function that result in specific cell types. Differentiation often involves a change in appearance as well as function.

Progenitor cells, such as stem cells, are not specified and so they become whatever you place them in! If you were to put stem cells on your eye for example, they would start forming eye cells (cool isn't it!?) You can find these cells in bone marrow, where they make all sorts of blood cells (white, red, immune cells, macrophages), in addition to embryonic cells of the fetus. Cell lines that have already been specified, such as skin cells, epithelial cells of a particular organ are specific for that area of the body since their DNA is blocked from doing anything else.

to answer your second question, protostomes have a determinate cleavage while deuterostomes have an indeterminate cleavage.