rectum

(noun)

the terminal part of the large intestine through which feces pass

Related Terms

Examples of rectum in the following topics:

  • Defecation Reflex

    • As additional fecal material enters the rectum, the rectal walls expand.
    • A sufficient increase in fecal material in the rectum causes stretch receptors from the nervous system, located in the rectal walls, to trigger the contraction of rectal muscles, relaxation of the internal anal sphincter, and an initial contraction of the skeletal muscle of the external sphincter .
    • If this urge is not acted upon, the material in the rectum is often returned to the colon by reverse peristalsis where more water is absorbed, thus temporarily reducing pressure and stretching within the rectum.
    • The rectum now contracts and shortens in peristaltic waves, thus forcing fecal material out of the rectum and out through the anal canal.

  • Elimination

    • The semi-solid waste is moved through the colon by peristaltic movements of the muscle and is stored in the rectum.
    • As the rectum expands in response to storage of fecal matter, it triggers the neural signals required to set up the urge to eliminate.
    • The solid waste is eliminated through the anus using peristaltic movements of the rectum.

  • Digestive System: Small and Large Intestines

    • The lower gastrointestinal tract includes the small and large intestines, rectum, anus, and accessory organs.
    • It has three parts: the cecum, the colon, and the rectum.
    • The rectum is the terminal end of the large intestine.
    • Two sphincters between the rectum and anus control elimination: the inner sphincter is involuntary, while the outer sphincter is voluntary.

  • Anatomy of the Large Intestine

    • From here it continues up the abdomen (ascending colon), then across the width of the abdominal cavity (transverse colon), and then it turns down (descending colon), continuing to its endpoint at the anus (sigmoid colon to rectum to anus) .
    • There are three bands, starting at the base of the appendix and extending from the cecum to the rectum.
    • Scheme of large intestine, with colon marked: cecum; (1) ascending colon; (2) transverse colon; (3) descending colon; (4) sigmoid colon; rectum and anus.

  • False and True Pelves

    • The true pelvis contains the pelvic colon, rectum, bladder, and some of the reproductive organs.
    • The rectum is at the back, in the curve of the sacrum and coccyx; the bladder is in front, behind the pubic symphysis.

  • Organs of the Digestive System

    • The upper digestive tract consists of the esophagus, stomach, and the small intestine, while the lower tract includes all of the large intestine, the rectum, and anus.
    • The lower GI tract contains the remainder of the system: the large intestine, rectum, and anus.
    • The compacted and dried-out waste passes to the rectum, and out of the body through the anus.

  • Histology of the Large Intestine

    • The large intestine consists of the cecum, colon, rectum, and anal canal.
    • These three bands start at the base of the appendix and extend from the cecum to the rectum.

  • Autonomic Plexuses

    • The inferior hypogastric plexus is a paired structure, with each situated on the side of the rectum in the male, and at the sides of the rectum and vagina in the female.

  • Urinary Bladder Cancer

    • In males, the base of the bladder lies between the rectum and the pubic symphysis.
    • It is superior to the prostate, and separated from the rectum by the rectovesical excavation.

  • Conic Sections in Polar Coordinates

    • where e is the eccentricity and l is half the latus rectum.