Defecation Process

Hye everyone ! how are you guys doing? sorry for the late late update. we were so busy managing our faculty's event which has ended today ! Alhamdulillah.... so today we will continue with another interesting topic like what has been stated in the post title. hey, it is not gross at all okay! (well maybe its kinda gross a little bit) BUT, don't you feel how interesting it could be? how all the foods you consume being excreted from your body through defecation? so, let us go details on the process....(don't imagine something else peeps)

Defecation also called bowel movement, the act of eliminating solid or semisolid waste materials (feces) from the digestive tract. In human beings, wastes are usually removed once or twice daily, but the frequency can vary from several times daily to three times weekly and remain within normal limits. Muscular contractions (peristaltic waves) in the walls of the colon move fecal material through the digestive tract to the rectum.

The structures that involved in defecation process are:

- Faeces formed in the rectum ( final segment of the large intestine)

- During defecation, faeces pass through anal canal to the anus:

• The anal canal is the final part of the rectum (2-3 cm to 1 inch long in adult).

- The internal sphincter muscle, a smooth muscle which is under involuntary control. It is      a thickened continuation of the circular muscle of the colon. It relaxes as a reflex                    response to distension of the distal rectum.

-       The external sphincter muscle, a skeletal muscle which is under voluntary control.

• These sphincter closed except during defecation (elimination of feces from the body)  

-the anus is the opening of the anal canal to the exterior of the body.

The cycle of defecation process can be described in terms of action from the digestive system, muscular system, cardiovascular aspects and the nervous system.

1.    When the external sphincter muscle is voluntarily relaxed for defecation, an increase in intra-abdominal pressure helps to expel feces from the body:

a.    With an intake of breath, the epiglottis (trapdoor in your throat, the opening between the vocal cords) closes over the trachea (windpipe, wide and hollow tube that connects the larynx or voice box).

b.    Voluntary contractions of the diaphragm and abdominal muscles also aid defecation by increasing the pressure within the abdomen and, in turn, increasing pressure on the walls of the sigmoid colon (part of the large intestine that is closest to the rectum and anus)

c.    Finally pelvic floor muscles relax. The rectum is straightened. Feces are expelled from the anus.  

SO FAR SO GOOD? we will proceed with the next info. please bear with us. 

What muscle are used to defecate?

Defecation is normally assisted by taking a deep breath and trying to expel this air against a closed glottis (Valsalva maneuver). This contraction of expiratory chest muscles, diaphragm, abdominal wall muscles, and pelvic diaphragm exerts pressure on the digestive tract.

Where is the poop stored in your body?

This area allows food to pass from the small intestine to the large intestine. The colon is where fluids and salts are absorbed and extends from the cecum to the rectum. The last part of the large intestine is the rectum, which is where faeces (waste material) is stored before leaving the body through the anus.

What is the muscles that push poop out?

The rectum shortens as material is forced into the anal canal and peristaltic waves push the feces out of the rectum. 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.

this image shows the summary of the defecation event.