Defecation is the act or process by which organisms eliminate solid, semisolid or liquid waste material (feces) from the digestive tract via the anus. WASTE is a Peer-to-peer and Friend-to-friend protocol and software application developed by Justin Frankel at Nullsoft in 2003 that features Feces, faeces, or fæces (see spelling differences) is a waste product from an animal's digestive tract expelled through the Anus The anus is an opening at the opposite end of an Animal 's Digestive tract from the Mouth. Humans expel feces with a frequency varying from a few times daily to a few times weekly; sloths can go a week without expelling. Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus The living sloths comprise six Species of medium-sized Mammals that live in Central and South America belonging to the families Waves of muscular contraction known as peristalsis in the walls of the colon move fecal matter through the digestive tract towards the rectum. Muscle (from Latin musculus, diminutive of mus "mouse" is contractile tissue of the body and is derived from the In the Esophagus After food is chewed into a bolus it is swallowed to move it into the esophagus The colon is a storage tube for solid wastes The main function of the colon appears to be extraction of Water and salts from Feces. The rectum (from the Latin rectum intestinum, meaning straight intestine) is the final straight portion of the Large intestine in some Mammals Undigested food may also be expelled this way; this process is called egestion.

The rectum ampulla (anatomically also: ampulla recti) acts as a temporary storage facility for the unneeded material. The rectal ampulla is the dilated section of the Rectum where Feces are stored until they are eliminated via the Anal canal. As the rectal walls expand due to the material filling it, stretch receptors from the nervous system located in the rectal walls stimulate the desire to defecate. The nervous system is a Network of specialized cells that communicate information about an animal's surroundings and itself This urge to defecate arises from the reflex contraction of rectal muscles, relaxation of the internal anal sphincter and an initial contraction of the skeletal muscle of the external sphincter. If the urge is not acted upon, the material in the rectum is often returned to the colon by reverse peristalsis where more water is absorbed and the faeces is stored until the next mass 'peristaltic' movement of the transverse and descending colon. The colon is a storage tube for solid wastes The main function of the colon appears to be extraction of Water and salts from Feces. Retroperistalsis is the reverse of the involuntary Smooth muscle contractions of Peristalsis. Water is a common Chemical substance that is essential for the survival of all known forms of Life. If defecation is delayed for a prolonged period the fecal matter may harden, resulting in constipation. Constipation, costiveness, or irregularity, is a condition of the Digestive system in which a person (or animal experiences hard Feces that

When the rectum is full, an increase in intra-rectal pressure forces the walls of the anal canal apart allowing the fecal matter to enter the canal. The anal canal is the terminal part of the Large intestine. It is situated between the Rectum and Anus, below the level of the Pelvic diaphragm The rectum shortens as material is forced into the anal canal and peristaltic waves push the feces out of the rectum. In the Esophagus After food is chewed into a bolus it is swallowed to move it into the esophagus The internal and external anal sphincters along with the puborectalis muscle, allow the feces to be passed by muscles pulling the anus up over the exiting feces. The Sphincter ani internus (or internal anal sphincter) is a muscular ring which surrounds about 2 The Sphincter ani externus ( external anal sphincter) is a flat plane of muscular fibers elliptical in shape and intimately adherent to the integument surrounding the margin The anus is an opening at the opposite end of an Animal 's Digestive tract from the Mouth.

Defecation is normally assisted by taking a deep breath and trying to expel this air against a closed glottis (Valsalva maneuver). The Valsalva maneuver is performed by forcibly exhaling against a closed airway This contraction of expiratory chest muscles, diaphragm, abdominal wall muscles, and pelvic diaphragm exert pressure on the digestive tract. The chest is a part of the Anatomy of humans and various other animals sometimes referred to as the Thorax. For other types of diaphragm see Diaphragm. In the Anatomy of Mammals the thoracic diaphragm is a sheet of Muscle The pelvis (pl pelvises or pelves) or pelvic girdle is the irregular bony structure located at the base of the spine (properly known Ventilation at this point temporarily ceases as the lungs push the chest diaphragm down in order to exert the pressure. In Respiratory physiology, ventilation (or ventilation rate) is the rate at which gas enters or leaves the Lung. Thoracic blood pressure rises and as a reflex response the amount of blood pumped by the heart decreases. Blood pressure is also the title of a short story by Damon Runyan in Guys and Dolls and Other Stories Death has been known to occur in cases where defecation causes the blood pressure to rise enough to cause the rupture of an aneurysm or to dislodge blood clots (see thrombosis). An aneurysm (or aneurism) is a localized blood-filled dilation (balloon-like bulge of a blood vessel caused by disease or weakening of the vessel wall Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products Thrombosis is the formation of a blood Clot ( Thrombus) inside a Blood vessel, obstructing the flow of Blood through the Circulatory Also, in release of the Valsalva maneuver blood pressure falls, this coupled often with standing up quickly to leave the toilet results in a common incidence of blackouts in this situation.

When defecating, the external sphincter muscles relax. The anal and urethal sphincter muscles are closely linked, and experiments by Dr. Harrison Weed at the Ohio State University Medical Center have shown that they can only be contracted together, not individually, and that they both show relaxation during urination. This explains why defecation is frequently accompanied with urination. Urination, also known as micturition, voiding, and more rarely emiction, is the process of disposing Urine from the Urinary bladder

Defecation may be involuntary or under voluntary control. Young children learn voluntary control through the process of toilet training. Toilet training, or potty training, is the process of training a young child to use the Toilet for Urination and Defecation. Once trained, loss of control causing fecal incontinence may be caused by physical injury (such as damage to the anal sphincter that may result from an episiotomy), intense fright, inflammatory bowel disease, impaired water absorption in the colon (see diarrhea), and psychological or neurological factors. Fecal incontinence is the loss of regular control of the Bowels. The Sphincter ani externus ( external anal sphincter) is a flat plane of muscular fibers elliptical in shape and intimately adherent to the integument surrounding the margin An episiotomy (ɛˌpiːziːˈɒtəmiː is a Surgical incision through the Perineum made to enlarge the Vagina and assist childbirth In Medicine, inflammatory bowel disease ( IBD) is a group of inflammatory conditions of the large intestine and Small intestine In Medicine, diarrhea, also spelled diarrhoea (see spelling differences) is frequent loose or liquid Bowel movements Acute diarrhea Psychology (from Greek grc ψῡχή psȳkhē, "breath life soul" and grc -λογία -logia) is an Academic and

The positions and modalities of defecation are culture-dependent. Culture (from the Latin cultura stemming from colere, meaning "to cultivate" generally refers to patterns of human activity and the symbolic In some regions of the world, such as South Asia, East Asia and rural parts of the Middle East, it is customary to squat (typically using squat toilets), while in most of the Western World sit-down toilets are used. The Middle East is a Subcontinent with no clear boundaries often used as a synonym to Near East, in opposition to Far East. A squat toilet (also known as an Eastern or floor-level toilet is a Toilet used by squatting, rather than sitting. The term Western world, the West or the Occident ( Latin: occidens -sunset -west as distinct from the Orient) can have multiple meanings A toilet is a Plumbing fixture and disposal system primarily intended for the disposal of the bodily wastes: Urine and fecal matter.

The anus and buttocks may be cleansed with toilet paper, similar paper products, or other absorbent material. The anus is an opening at the opposite end of an Animal 's Digestive tract from the Mouth. The buttocks (singular buttock) are rounded portions of the anatomy located on the posterior of the Pelvic region of the Apes including Humans Anal cleansing is the important hygienic practice of cleaning the anus after defecation Toilet paper is a soft paper product used to maintain Personal hygiene after human Defecation or Urination. In some cultures water is used (e. g. as with a bidet) either in addition or exclusively. A bidet is a low-mounted Plumbing fixture or type of Sink intended for Washing the Genitalia, inner Buttocks, and Anus. In Japan, some toilets known as washlets are designed to wash and dry the anus of the user after defecation (see anal cleansing). There are two styles of Toilets commonly found in Japan. The oldest type is a simple Squat toilet, which is still common in public conveniences. Anal cleansing is the important hygienic practice of cleaning the anus after defecation

References

• Deeb, Benjamin (2004). "Healthy to the Core: How to Measure Effective Defecation. " Greenwood Press.
• Widmaier, Raff, Strang (2006). "Vanders Human Physiology, the mechanisms of body function. Chapter 15. McGraw Hill.

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