No water has been discovered on either planet yet.
<span>The correct answer is B. crepuscular activity. Crepuscular refers to animals and birds that are active at night, during twilight. So, these little birds don't usually travel large distances during the day, first of all, because they can't due to their small wings and plump bodies, and second of all, in order to avoid getting eating by a larger bird or animal. So they are usually nocturnal birds that live during the night.</span>
Answer:
of the low pH of the vagina.
Explanation:
The pH of the vagina is maintained at highly acidic levels to prevent the germ buildup. The range of vaginal pH is around 3.8 to 4.5. The very low pH of the vagina creates a hostile environment for sperms and most of the sperms are killed as they enter the vagina due to the acidic pH.
Apart from supplementing the sperms with energy, cervical mucus serves to protect the sperms from the hostile conditions of the vagina. The cervical mucus has an alkaline pH at or near the ovulation to protect sperms from acidic pH of the vagina and to facilitate fertilization.
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