Studying cellular processes in a living C. elegans offers the advantage of a physiological environment in which these processes occur. However, because of the small size of the animal, and because the cuticle of the animal is a significant permeability barrier, many experiments are difficult or impossible to perform. Thus, for example,
rapid modulation of cellular components using drugs is nearly impossible. Furthermore, studies of a particular process may be hampered by other physiological events surrounding the cell being examined, making results sometimes difficult to interpret. Cell culture offers an alternative to in vivo studies, where problems such as those discussed above are obviated (Christensen et al., 2002; Zhang et al., 2002). Interpretation of experiments using cultured cells, of course, suffers from the non-physiological conditions under which the cells are grown. Thus, culture studies and in vivo studies can be complementary, and together can yield significant insight into cell biological questions.