Phagocytosis is the process by which a cell engulfs and consumes bacteria, foreign material, and cellular debris. When a phagocyte identifies a target, it extends a pseudopod, which wraps around the target and engulfs it, forming a phagosome containing the target material. The phagosome meets and fuses with a lysosome, which releases lysosomal enzymes into the phagosome. These lysosomal enzymes break down the target material, leaving behind particles called a residual body. These particles are released by exocytosis.