lower gastrointestinal tract

Examples of lower gastrointestinal tract in the following topics:

• Anatomy of the Digestive System

  • The human gastrointestinal tract refers to the stomach and intestine, and sometimes to all the structures from the mouth to the anus.
  • The upper gastrointestinal tract consists of the esophagus, stomach, and duodenum.
  • The lower gastrointestinal tract includes most of the small intestine and all of the large intestine.
  • The ligament of Treitz is sometimes used to divide the upper and lower GI tracts.
  • This image shows the position of the small intestine in the gastrointestinal tract.

• Organs of the Digestive System

  • The organs of the digestive system can be divided into upper and lower digestive tracts.
  • The major organs within our digestive system can be split into two major segments of this tube: the upper gastrointestinal tract, and the lower gastrointestinal tract.
  • The upper gastrointestinal, or GI, tract is made up of three main parts:
  • The exact dividing line between upper and lower tracts can vary, depending on which medical specialist is examining the GI tract.
  • The bolus gets swallowed, and begins its journey through the upper gastrointestinal tract.

• Occult Blood

  • Fecal occult blood (FOB) refers to not-visibly-apparent blood in the feces that may indicate problems with the gastrointestinal tract.
  • The purpose of fecal occult blood testing (FOBT) is to detect subtle blood loss in the gastrointestinal tract, anywhere from the mouth to the colon.
  • Positive tests ("positive stool") may result from either upper gastrointestinal bleeding or lower gastrointestinal bleeding and warrant further investigation for peptic ulcers or a malignancy (such as colorectal cancer or gastric cancer).
  • Gastrointestinal bleeding has many potential sources, and positive test results usually lead to further testing for the bleeding site, usually looking at possible lower gastrointestinal bleeding before looking at upper gastrointestinal bleeding causes, unless there are other clinical clues.
  • In the event of a positive fecal occult blood test, the next step in the workup is a form of visualization of the gastrointestinal tract by one of several means: sigmoidoscopy, an examination of the rectum and lower colon with a lighted instrument to look for abnormalities, such as polyps; colonoscopy, a more thorough examination of the rectum and entire colon; virtual colonoscopy; endoscopy refers to upper gastrointestinal endoscopy sometimes performed with chromoendoscopy; and double contrast barium enema: a series of X-rays of the colon and rectum.

• Plexuses

  • The brachial plexus is formed by the ventral rami of C5–C8 and the T1 spinal nerves, and lower and upper halves of the C4 and T2 spinal nerves.
  • It is interconnected with the lower part of sacral plexus.
  • In addition, the celiac plexus serves the internal organs, and Auerbach's plexus serves the gastrointestinal tract.

• X-Ray Studies of the GI Tract

  • Upper GI series, also upper gastrointestinal (GI) tract radiography, is a radiologic examination of the upper gastrointestinal tract.
  • Upper GI series, also known as upper gastrointestinal (GI) tract radiography, is a radiologic examination of the upper gastrointestinal tract .
  • The upper GI tract consists of the esophagus, stomach, and duodenum.
  • Describe the process and purpose of taking X-rays of the GI tract

• Mucosa

  • The mucosa, composed of simple epithelium cells, is the innermost layer of the gastrointestinal (GI) tract.
  • It is the absorptive and secretory layer of the GI tract.
  • The GI tract is composed of four layers.
  • The mucosae (singular: mucosa) are highly specialized in each organ of the gastrointestinal tract in order to deal with different digestive tract conditions.
  • Describe the structure and function of the mucosa of the GI tract

• Dietary Fiber

  • Dietary fiber interacts with the contents of the gastrointestinal tract, and it changes how other nutrients and chemicals are absorbed.
  • In addition to lowering the risk of death from heart disease, adequate consumption of fiber-containing foods, especially grains, also appeared to reduce the incidence of infectious and respiratory illnesses.
  • Particularly among males, fiber consumption lowered the risk of cancer-related death.
  • Dietary fiber acts by changing the nature of the contents of the gastrointestinal tract and by changing how other nutrients and chemicals are absorbed.
  • It is fermented by bacteria in the digestive tract.

• Gastrointestinal Reflex Pathways

  • The digestive system functions via a system of long reflexes, short reflexes, and extrinsic reflexes from gastrointestinal (GI) peptides working together.
  • The gastrocolic reflex is the physiological reflex controlling the motility, or peristalsis, of the gastrointestinal tract.
  • The gastroileal reflex is a third type of gastrointestinal reflex.
  • They act on a variety of tissues including the brain, digestive accessory organs, and the GI tract.
  • The gastrocolic reflex is one of a number of physiological reflexes controlling the motility, or peristalsis, of the gastrointestinal tract.

• Organization of Motor Neuron Pathways

  • There are upper and lower motor neurons in the corticospinal tract.
  • The midbrain nuclei include four motor tracts that send upper motor neuronal axons down the spinal cord to lower motor neurons.
  • The function of lower motor neurons can be divided into two different groups: the lateral corticospinal tract and the anterior corticalspinal tract.
  • The lateral tract contains upper motor neuronal axons that synapse on the dorsal lateral lower motor neurons, which are involved in distal limb control.
  • The pyramidal tract is visible in red, and pyramidal decussation is labeled at lower right.

• Development of Metabolism

  • The gut or gastrointestinal tract is an endoderm-derived structure.