“…Embryo and eggs of sea urchin have been used as a model for studying cell division and embryologic development for several years. This model has also been utilized to detect the cytotoxic and teratogenic activities of new compounds [10,11]. At fertilization, egg undergoes a complex series of morphological, physiological, biochemical and, in many cases, morphogenetic changes that ultimately lead to differentiation of the new individual [17].…”