Ingestion by phagocytes is the fate of most cells that undergo apoptosis. During apoptosis, there are many changes on the surface of apoptotic cells, including the exposure of phosphatidylserine, the alteration of membrane carbohydrates and the redistribution or clustering of glycoproteins, which are leading to recognition and uptake by phagocytes. Many engulfment receptors have been implicated and appear to be divided into two categories, involved in tethering the apoptotic cell or triggering an uptake mechanism related to macropinocytosis. The process of uptake may vary with the apoptotic and engulfing cell types. At least seven engulfment genes in C.elegans have mammalian equivalents, and represent elements of signaling pathways involved in uptake, which have been proposed to define two parallel and partially redundant pathways. The mutation of engulfment genes can change the process of apoptosis. The defections of phagocytosis can affect the body's normal immune response.