Macrophages are phagocytic cells that are common in connective tissue. Phagocytosis is the process by which cells bind and internalize microbes, cell debris, and apoptotic cells.
An isolated macrophage as seen by scanning electron microscopy (SEM). It has both membrane-adherent and partially ingested bacteria. Note the close adhesion of the plasma membrane of the macrophage to the bacterium being phagocytized.