The vertebrate kidney helps to keep the acidity of the body fluids constant by varying the amount of hydrogen ions (H+) it secretes into the urine. You can confidently predict that this aspect of kidney function, like other mechanisms of homeostasis, will be controlled by .

Explanation:

a negative feedback mechanism

italy's population growth rate is almost at zero, the national statistics agency, istat, said on monday, mainly due to a dwindling birth rate.

answer by yourhope:

answer is

human impact on the environment can be seen in the deterioration of the !

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