White blood cells, or leukocytes, contain the same organelles as eukaryotic cells, such as the Golgi apparatus, mitochondria, a nucleus and nucleolus, centrioles, rough endoplasmic reticulum, smooth endoplasmic reticulum and peroxisomes. White blood cells are important cells in the immune system, explains the University of Rochester Medical Center.
Lysosomes are the most important organelles in white blood cells due to the function of the cell. They produce enzymes that the leukocyte uses to digest microorganisms and antigens that cause disease, such as viruses or bacteria. Peroxisomes also contribute to this as well as producing peroxides that allow the cell to cleanse itself, according to TutorVista.