It keeps them out side the body to maintain the correct temperature.
Answer:
Both conditions are caused by an inability of the body to produce adequate acetylcholine.
Explanation:
Botulism is a potentially fatal condition caused by the toxin of bacteria <em>Clostridium botulinum</em>. Early symptoms are weakness, slurred speech, blurred vision etc. It may lead to vomiting, abdominal swelling and respiratory failure if not treated. The toxin hinders the release of neurotransmitter acetylcholine due to which motor neurons are not able to send signals to muscle cells. Muscles are not able to function properly due to which paralysis occurs.
Myasthenia gravis is also a neuromuscular condition like botulism. But unlike botulism release of acetylcholine is not hindered here. The receptors for acetylcholine are destroyed or altered by body's own immune system. Acetylcholine despite being present is not able to relay the signal which leads to muscle weakness. Symptoms are almost similar to those of botulism.
Answer:
Extrinsic regulatory mechanisms are external and depend on the firing of some factor outside the population itself. Among them are interspecific competition, food and space restrictions, very strong climatic variations, weathering and inharmonious relationships with other populations (parasitism and predatism).
Good examples of interspecific competition appear when rabbits, caves, rats compete for the same plant, or different fish and birds, such as the heron, vie for the same species of smaller fish. This is because these different species keep their populations in the same ecological niche. Competition is often so strong that some species eventually, as one example of an extrinsic homeostatic mechanism overriding an intrinsic homeostatic process is their disappearance or migration to other regions.
In this competition, the presence of adaptations among individuals in the population that promote better food search, speed, vision, and others can make the difference between elimination and survival.