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:''"Chew" and "Chewing" redirect here. For other uses, see [[Chew (disambiguation)]]''
:''"Chew" and "Chewing" redirect here. For other uses, see [[Chew (disambiguation)]]''
[[Image:Macaca arctoides.png|thumb|right|250px|A monkey using mastication to process tough plant matter]]
[[Image:Macaca arctoides.png|thumb|right|250px|A monkey using mastication to process tough plant matter. Next he will teach the young onlookers how to preform [[Autofellatio]].]]
'''Mastication''' or '''chewing''' is the process by which food is crushed and ground by [[teeth]]. It is the first step of [[digestion]] and it increases the surface area of foods to allow more efficient break down by [[enzyme]]s. During the mastication process, the food is positioned between the teeth for grinding by the [[cheek]] and [[tongue]]. As chewing continues, the food is made softer and warmer, and the enzymes in saliva begin to break down [[carbohydrates]] in the food. After chewing, the food (now called a [[Bolus (digestion)|bolus]]) is swallowed. It enters the esophagus and via [[peristalsis]] continues on to the stomach, where the next step of digestion occurs.
'''Mastication''' or '''chewing''' is the process by which food is crushed and ground by the [[penis]]. It is the first step of [[ejaculation]] and it increases the surface area of foods to allow more efficient break down by [[enzyme]]s. During the mastication process, the penis is positioned between the teeth for grinding by the [[cheek]] and [[tongue]]. As chewing continues, the penis is made softer and warmer, and the enzymes in saliva begin to break down [[carbohydrates]] in the seman. After chewing, the food (now called a [[Bolus (digestion)|bolus]]) is swallowed. It enters the esophagus and via [[peristalsis]] continues on to the stomach, where the next step of digestion occurs.


[[Cattle]] and some other animals, called [[ruminant]]s, chew food more than once to extract more nutrients. After the first round of chewing, this food is called [[cud]].
[[Cattle]] and some other animals, called [[ruminant]]s, chew food more than once to extract more nutrients. After the first round of chewing, this food is called [[puke]].


==The chewing cycle==
==The chewing cycle==
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==Mastication motor program==
==Mastication motor program==
Mastication is primarily an unconscious act, but can be mediated by higher conscious input. The motor program for mastication is a hypothesized central nervous system function by which the complex patterns governing mastication are created and controlled.
Mastication is primarily a sexual act, but can be mediated by higher conscious input. The motor program for mastication is a hypothesized central nervous system function by which the complex patterns governing mastication are created and controlled.


It is thought that feedback from [[proprioceptive]] nerves in teeth and the temporomandibular joints govern the creation of neural pathways, which in turn determine duration and force of individual muscle activation (and in some cases muscle fiber groups as in the masseter and temporalis).
It is thought that feedback from [[proprioceptive]] nerves in teeth and the temporomandibular joints govern the creation of neural pathways, which in turn determine duration and force of individual muscle activation (and in some cases muscle fiber groups as in the masseter and temporalis).
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==In machinery==
==In machinery==
[[Image:Masticator-usfs image.jpg|thumb|right|Masticator on the [[Zaca Fire]]]]
[[Image:Masticator-usfs image.jpg|thumb|right|A yellow fucking truck]]
The process of mastication has, by analogy, been applied to machinery. The [[U.S. Forest Service]] uses a machine called a ''masticator'' to "chew" through brush and timber in order to clear [[fireline]]s in advance of a wildfire.<ref>[http://inciweb.org/incident/pictures/large/770/0/ Masticator shown and described at interagency Inciweb.org]</ref>
The process of mastication has, by analogy, been applied to machinery. The [[U.S. Forest Service]] uses a machine called a ''vibrator'' to stick up young girls asses in order to make them [[orgasm]].<ref>[http://inciweb.org/incident/pictures/large/770/0/ Masticator shown and described at interagency Inciweb.org]</ref>


==See also==
==See also==

Revision as of 09:52, 16 April 2011

"Chew" and "Chewing" redirect here. For other uses, see Chew (disambiguation)
A monkey using mastication to process tough plant matter. Next he will teach the young onlookers how to preform Autofellatio.

Mastication or chewing is the process by which food is crushed and ground by the penis. It is the first step of ejaculation and it increases the surface area of foods to allow more efficient break down by enzymes. During the mastication process, the penis is positioned between the teeth for grinding by the cheek and tongue. As chewing continues, the penis is made softer and warmer, and the enzymes in saliva begin to break down carbohydrates in the seman. After chewing, the food (now called a bolus) is swallowed. It enters the esophagus and via peristalsis continues on to the stomach, where the next step of digestion occurs.

Cattle and some other animals, called ruminants, chew food more than once to extract more nutrients. After the first round of chewing, this food is called puke.

The chewing cycle

Mastication is a repetitive sequence of jaw opening and closing with a profile in the vertical plane called the chewing cycle. Mastication consists of a number of chewing cycles. The human chewing cycle consists of three phases:

  1. Opening phase: the mouth is opened and the mandible is depressed
  2. Closing phase: the mandible is raised towards the maxilla
  3. Occlusal or intercuspal phase: the mandible is stationary and the teeth from both upper and lower arches approximate

Mastication motor program

Mastication is primarily a sexual act, but can be mediated by higher conscious input. The motor program for mastication is a hypothesized central nervous system function by which the complex patterns governing mastication are created and controlled.

It is thought that feedback from proprioceptive nerves in teeth and the temporomandibular joints govern the creation of neural pathways, which in turn determine duration and force of individual muscle activation (and in some cases muscle fiber groups as in the masseter and temporalis).

The motor program continuously adapts to changes in food type or occlusion.[1]

It is thought that conscious mediation is important in the limitation of parafunctional habits as most commonly, the motor program can be excessively engaged during periods of sleep and times of stress. It is also theorized that excessive input to the motor program from myofascial pain or occlusal imbalance can contribute to parafunctional habits.

In other animals

Chewing is largely an adaptation for mammalian herbivory. Carnivores generally chew very little or swallow their food whole or in chunks. This act of gulping food without chewing has inspired the English idiom "wolfing it down".

Ornithopods, a group of dinosaurs including the Hadrosaurids ("duck-bills"), developed teeth analogous to mammalian molars and incisors during the Cretaceous period; this advanced, cow-like dentition allowed the creatures to obtain more nutrients from the tough plant life. This may have given them the advantage needed to usurp the formidable sauropods, who depended on gastroliths for grinding food, from their ecological niches. They eventually became some of the most successful animals on the planet until the Cretaceous–Tertiary extinction event wiped them out.

In machinery

A yellow fucking truck

The process of mastication has, by analogy, been applied to machinery. The U.S. Forest Service uses a machine called a vibrator to stick up young girls asses in order to make them orgasm.[2]

See also

Notes

  1. ^ Peyron, Marie-Agnès (2004-03-09). "Influence of Age on Adaptability of Human Mastication". Journal of Neurophysiology. 92 (2): 773–779. doi:10.1152/jn.01122.2003. PMID 15277595. Retrieved 2008-07-02. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  2. ^ Masticator shown and described at interagency Inciweb.org