IN: It is important to note that mithridatism is not effective against all types of poison (immunity generally is only possible with biologically complex types which the immune system can respond to) and, depending on the toxin, the practice can lead to the lethal accumulation of a poison in the body. Results depend on how each poison is processed by the body, ie, on how the toxic compound is metabolized or passed out of the body. In some cases, it is possible to build up tolerance against specific non-biological poisons. For some poisons, this involves conditioning the liver to produce more of the particular enzymes that deal with these poisons (for example alcohol). Another mechanism involves conditioning the target tissues of the poisons. These methods do not work for all non-biological poisons. Exposure to certain toxic substances, such as hydrofluoric acid and heavy metals, is either lethal or has little to no effect, and thus cannot be used in this way at all. Arsenic is a notable exception with some people actually having a genetic adaptation granting them higher resistance which can be replicated with mithridatism. In addition, simple toxins that work through chemical processes that bypass the immune system cannot be dealt with (good example would be the variants of cyanide).
can you build up a resistance to cyanide?

OUT: no

IN: While mentioned in passing throughout later seasons, Burke officially returns in the tenth season in order to conclude Cristina Yang's departure from the series.
does preston burke ever come back to grey anatomy?

OUT: yes

IN: This species is indigenous to more coastal regions of southern Africa and east Africa. The eastern green mamba's range extends from Kenya south through Tanzania, Mozambique, Malawi, eastern Zimbabwe, eastern Zambia into South Africa as far as southern Natal and northern Pondoland. It can also be found in Zanzibar. The distribution of this species is assumed to be continuous, but reports seem to be scarce in regions within the species' range.
do we have green mamba in south africa?

OUT: yes

IN: The great white shark has no known natural predators other than, on very rare occasions, the killer whale. The great white shark is arguably the world's largest known extant macropredatory fish, and is one of the primary predators of marine mammals. It is also known to prey upon a variety of other marine animals, including fish and seabirds. It is the only known surviving species of its genus Carcharodon, and is ranked first in having the most recorded shark bite incidents on humans.
do great white sharks have any natural predators?

OUT:
no