Mouth : Lip
The mouth is the opening through which an animal takes in food. It is usually located in the head, but not always; the mouth of a planaria[?] is in the middle of its belly.Most animals have a complete digestive system, with a mouth at one end and an anus at the other. Which end forms first in ontogeny is a criterion used to classify animals into protostome and deuterostome.
Some animals, such as the cnidarians and the planaria, have no anus. They expel waste through the mouth, or as do brachiopods, which have very efficient digestive systems, roll it around in the stomach until it's finished.
Some animals, such as the tapeworm, don't even have a mouth. The tapeworm lives inside the digestive system, so it doesn't need its own digestive system.
In many animals, the mouth has mouthparts[?] to chew food, hold food, or inject poison. In arthropods, they are external modified legs; in gnathostome vertebrates, they are internal.
The horny structures covering the mouth of a bird compose its beak or bill.
The human mouth is covered by an upper and lower lip. They play an important role in talking, facial expression, kissing, drinking (especially with a straw), oral sex, smoking. Infants are born with a sucking reflex, by which they instinctively[?] know to suck for nourishment using their lips and jaw. Lips are often adorned with lipstick.
According to etiquette the mouth is kept closed during chewing.
See also Tongue, Teeth, Lip piercing.
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supposed relatively sterile region west of the Missouri River
that the idea of absolute sterility was a mistaken one;
advancement of civilization there, railroads would never have
inherently not a desert in its most rigid definition, but a
genius of agriculture, made possible alone by the building of
indeed be a howling wilderness. As the late Sidney Dillon,
article on "The West and the Railroads" in the _North American Review_
Like many other great truths, this is so well known to the
and the younger portions do not comprehend or appreciate it.
as if they had always existed, and were matters of course.
years, but people light their fires to-day without a thought
is of such inestimable value, and yet remained so long unknown.
New York, Philadelphia, or Chicago, eats, sleeps, surveys
alights in Portland or San Francisco without any just
have required weeks of toilsome travel to go over the same
of being lost in the wilderness, plundered by robbers, or
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for a horse to do the same? The railway does it at a cost of
direct relation with hungry and opulent Liverpool, and makes
The world should, therefore, thank the railway for the
thank the railway for the opportunity to sell wheat.
.
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