Neither species can survive without the other, a relationship known as obligate mutualism.
As obligate anaerobes, clostridia are rather inefficient in energy production.
As obligate parasites, entomopathogenic nematodes (EPN) rely on insect hosts to complete their development.
As obligate intracellular parasites, viruses are completely dependent upon a host cell for their replication.
As obligate intracellular parasites, viruses require cell in which to replicate.
Grace's insect cell culture medium supplemented with lactalbumin hydrolysate and yeastolate has allowed growth of several species which until recently were referred to as obligate parasites.
As obligate intracellular parasites, viruses orchestrate intricate sets of reactions that recruit and usurp cellular functions in such a way as to facilitate their replication.
Moreover, phenological shifts in flowering/fruiting periods may severely affect the associated community of a plant (Miller-Rushing et al. 2010), particularly for interacting species such as obligate mutualistic partners.
As obligate parasites, TIPs would transmit via the same risk factors and transmission routes as wild type viruses, automatically reaching high-risk populations, and thereby substantially limiting viral transmission even in resource-poor settings.
The occurrence of facultative as well as obligate temporary pond species suggested that this habitat may play an important role in the interchange of species between waterbodies at the landscape scale.
Those adaptations, which evolved over tens of millions of years, are thought to be what allows felines, as obligate carnivores, to digest and live solely on a diet of animal meat.
