Both systems make use of internal and external concepts. Systems are available for both internal and external applications. Main battle tanks have internal and external storage space. It may be due to a combination of internal and external causes. There is a fundamental distinction between internal and external digestion. This condition does not result in any imbalance between internal and external genitalia. Damselflies have a variety of internal and external parasites. Ecosystems are controlled by external and internal factors. The conceptual view provides a level of indirection between internal and external. Tribes are susceptible to overlapping external and internal definition. Seed germination depends on both internal and external conditions. He identifies two forms of hegemony, internal and external. Aquatic species use either internal or external fertilization. Development is overseen by internal and external producers. Private schools also began to desegregate in response to growing internal and external pressure.