Because homeostasis is vital for survival, mechanisms have evolved that maintain a stable internal environment.

Redundant mechanisms

To maintain homeostasis, redundant mechanisms are present in the body so that when one of the systems fails, other complementary or backup systems can help to compensate and ensure the survive of the organism by maintaining homeostasis. Examples of these redundant systems involve blood pressure regulation, temperature regulation, breathing and pH control in the body during exercise.

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Because the earth is not round ,but it may seem round when viewed from ,our planet but true some points earth is not round was an oblate spheroid -a square that it squashed as globe however is not even a perfect oblate spheroid.in fact isaac newton's first proposed that earth was not perfectly round but it was an oblate spheroid instead.that mean a square that is squashed as its poles and swollen at the