"forms the mesentery proper. The ventral mesentery, located in the region of the terminal part of the esophagus, the stomach and the upper part of the duodenum, is derived from the septum transversum. Growth of the liver into the mesenchyme of the septum transversum divides the ventral mesentery into the lesser omentum, extending from the lower portion of the esophagus, the stomach, and the upper portion of the duodenum to the liver and the falciform ligament, extending from the liver to the ventral body wall. Development of the digestive system The development of the digestive system concerns the epithelium of"
"blood in the colon of the large intestine. The waste products of digestion (feces) are defecated from the anus via the rectum. There are several organs and other components involved in the digestion of food. The organs known as the accessory digestive glands are the liver, gall bladder and pancreas. Other components include the mouth, salivary glands, tongue, teeth and epiglottis. The largest structure of the digestive system is the gastrointestinal tract (GI tract). This starts at the mouth and ends at the anus, covering a distance of about nine (9) metres. The largest part of the GI tract is"
"are not as clear and the terms middle intestine or mid-gut may be used instead of jejunum. ""Jejunum"" is derived from the Latin word ""jējūnus"", meaning ""fasting."" It was so called because this part of the small intestine was frequently found to be void of food following death, due to its intensive peristaltic activity relative to the duodenum and ileum. The Early Modern English adjective ""jejune"" is derived from this word. Jejunum The jejunum () is the second part of the small intestine in humans and most higher vertebrates, including mammals, reptiles, and birds. The jejunum lies between the duodenum"
"small intestine, and large intestine. However, the complete human digestive system is made up of the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary glands, pancreas, liver and gallbladder). The tract may also be divided into foregut, midgut, and hindgut, reflecting the embryological origin of each segment. The whole human GI tract is about nine metres (30 feet) long at autopsy. It is considerably shorter in the living body because the intestines, which are tubes of smooth muscle tissue, maintain constant muscle tone in a halfway-tense state but can relax in spots to allow for local distention"
"Gastrovascular cavity The gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Cnidaria (including jellyfish and corals) and Platyhelminthes (flatworms). The cavity may be extensively branched into a system of canals. In cnidarians, the gastrovascular system is also known as the coelenteron, and is commonly known as a ""blind gut"" or ""blind sac"", since food enters and waste exits through the same orifice. The radially symmetrical cnidarians have a sac-like body in two distinct layers, the epidermis and gastrodermis, with a jellylike layer called the mesoglea between. Extracellular digestion takes place within the"
"Esophagus The esophagus (American English) or oesophagus (British English) (), commonly known as the food pipe or gullet (gut), is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach. The esophagus is a fibromuscular tube, about 25 centimetres long in adults, which travels behind the trachea and heart, passes through the diaphragm and empties into the uppermost region of the stomach. During swallowing, the epiglottis tilts backwards to prevent food from going down the larynx and lungs. The word ""esophagus"" is the Greek word οἰσοφάγος , meaning ""gullet"". The wall of"
"organ systems. The digestive system consists of a mouth, pharynx, and a gastrovascular cavity. The mouth is located in the center of the underside of the body. Digestive enzymes are secreted from the mouth to begin external digestion. The pharynx connects the mouth to the gastrovascular cavity. This structure branches throughout the body allowing nutrients from food to reach all extremities. Planaria eat living or dead small animals that they suck up with their muscular mouths. Food passes from the mouth through the pharynx into the intestines where it is digested by the cells lining the intestines. Then its nutrients"
"the pyloric sphincter of the stomach to the anus and, as in other mammals, consists of two segments, the small intestine and the large intestine. In humans, the small intestine is further subdivided into the duodenum, jejunum and ileum while the large intestine is subdivided into the, cecum, ascending, transverse, descending and sigmoid colon, rectum, and anal canal. The small intestine begins at the duodenum and is a tubular structure, usually between 6 and 7 m long. Its mucosal area in an adult human is about 30 m. Its main function is to absorb the products of digestion (including carbohydrates,"
"Major duodenal papilla The major duodenal papilla is an opening of the Common bile duct and Pancreatic duct into the duodenum. The major duodenal papilla is, in most people, the primary mechanism for the secretion of bile and other enzymes that facilitate digestion. The major duodenal papilla is situated in the second part of the duodenum, 7–10 cm from the pylorus, at the level of the second or third lumbar vertebrae. It is surrounded by the sphincter of Oddi, and receives a mixture of pancreatic enzymes and bile from the Ampulla of Vater, which drains both the pancreatic duct and"
"Duodenum The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear, and the terms anterior intestine or proximal intestine may be used instead of duodenum. In mammals the duodenum may be the principal site for iron absorption. The duodenum precedes the jejunum and ileum and is the shortest part of the small intestine. In humans, the duodenum is a hollow jointed tube about 25–38 cm (10–15 inches) long connecting the stomach to the jejunum. It begins with the duodenal"
"different regions. In traditional Chinese medicine, the small intestine is a yang organ. Small intestine The small intestine or small bowel is the part of the gastrointestinal tract between the stomach and the large intestine, and is where most of the end absorption of food takes place. The small intestine has three distinct regions – the duodenum, jejunum, and ileum. The duodenum is the shortest part of the small intestine and is where preparation for absorption begins. It also receives bile and pancreatic juice through the pancreatic duct, controlled by the sphincter of Oddi. The primary function of the small"
"Small intestine The small intestine or small bowel is the part of the gastrointestinal tract between the stomach and the large intestine, and is where most of the end absorption of food takes place. The small intestine has three distinct regions – the duodenum, jejunum, and ileum. The duodenum is the shortest part of the small intestine and is where preparation for absorption begins. It also receives bile and pancreatic juice through the pancreatic duct, controlled by the sphincter of Oddi. The primary function of the small intestine is the absorption of nutrients and minerals from food, using small finger-like"
"large parts. The upper gastrointestinal tract consists of the mouth, pharynx, esophagus, stomach, and duodenum. The exact demarcation between the upper and lower tracts is the suspensory muscle of the duodenum. This differentiates the embryonic borders between the foregut and midgut, and is also the division commonly used by clinicians to describe gastrointestinal bleeding as being of either ""upper"" or ""lower"" origin. Upon dissection, the duodenum may appear to be a unified organ, but it is divided into four segments based upon function, location, and internal anatomy. The four segments of the duodenum are as follows (starting at the stomach,"
"cleaving it to form trypsin; further cleavage results in chymotripsin. The lower gastrointestinal tract (GI), includes the small intestine and all of the large intestine. The intestine is also called the bowel or the gut. The lower GI starts at the pyloric sphincter of the stomach and finishes at the anus. The small intestine is subdivided into the duodenum, the jejunum and the ileum. The cecum marks the division between the small and large intestine. The large intestine includes the rectum and anal canal. Partially digested food starts to arrive in the small intestine as semi-liquid chyme, one hour after"
"Jejunum The jejunum () is the second part of the small intestine in humans and most higher vertebrates, including mammals, reptiles, and birds. The jejunum lies between the duodenum and the ileum and is considered to start at the suspensory muscle of the duodenum , a location called the duodenojejunal flexure. The division between the jejunum and ileum is not anatomically distinct due to the fact that in adult humans, the small intestine is usually 6-7m long, about two-fifths of which (2.5 m) is the jejunum. The interior surface of the jejunum— which is exposed to ingested food— is covered"
"Greater omentum The greater omentum (also the great omentum, omentum majus, gastrocolic omentum, epiploon, or, especially in animals, caul) is a large apron-like fold of visceral peritoneum that hangs down from the stomach. It extends from the greater curvature of the stomach, passing in front of the small intestines and doubles back to ascend to the transverse colon before reaching to the posterior abdominal wall. The greater omentum is larger than the lesser omentum, which hangs down from the liver to the lesser curvature. The common anatomical term ""epiploic"" derives from ""epiploon"", from the Greek ""epipleein"", meaning to float or"
"Human digestive system The human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary glands, pancreas, liver, and gallbladder). Digestion involves the breakdown of food into smaller and smaller components, until they can be absorbed and assimilated into the body. The process of digestion has many stages. The first stage is the cephalic phase of digestion which begins with gastric secretions in response to the sight and smell of food. The next stage starts in the mouth. Chewing, in which food is mixed with saliva, begins the mechanical process of digestion. This produces"
"Large intestine The large intestine, also known as the large bowel, is the last part of the gastrointestinal tract and of the digestive system in vertebrates. Water is absorbed here and the remaining waste material is stored as feces before being removed by defecation. The colon is the largest portion of the large intestine, so many mentions of the large intestine and colon overlap in meaning whenever anatomic precision is not the focus. Most sources define the large intestine as the combination of the cecum, colon, rectum, and anal canal. Some other sources exclude the anal canal. In humans, the"
"Stomach The stomach (from ancient Greek στόμαχος, ""stomachos,"" ""stoma"" means mouth) is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital digestive organ. In the digestive system the stomach is involved in the second phase of digestion, following mastication (chewing). In humans and many other animals, the stomach is located between the oesophagus and the small intestine. It secretes digestive enzymes and gastric acid to aid in food digestion. The pyloric sphincter controls the passage of partially digested food (chyme) from"
"large intestine begins in the right iliac region of the pelvis, just at or below the waist, where it is joined to the end of the small intestine at the cecum, via the ileocecal valve. It then continues as the colon ascending the abdomen, across the width of the abdominal cavity as the transverse colon, and then descending to the rectum and its endpoint at the anal canal. Overall, in humans, the large intestine is about long, which is about one-fifth of the whole length of the gastrointestinal tract. The colon is the last part of the digestive system. It"
"canal is the foregut (element 27 in numbered diagram), or stomodaeum. The foregut is lined with a cuticular lining made of chitin and proteins as protection from tough food. The foregut includes the buccal cavity (mouth), pharynx, esophagus and crop and proventriculus (any part may be highly modified), which both store food and signify when to continue passing onward to the midgut. Digestion starts in buccal cavity (mouth) as partially chewed food is broken down by saliva from the salivary glands. As the salivary glands produce fluid and carbohydrate-digesting enzymes (mostly amylases), strong muscles in the pharynx pump fluid into"
"of the digestive system, and consists of the mouth and pharynx. The mouth includes a radula, and in most cases, also a pair of jaws. The pharynx can be very large, especially in carnivorous species. Many carnivorous species have developed a proboscis, containing the oral cavity, radula, and part of the oesophagus. At rest, the proboscis is enclosed within a sac-like sheath, with an opening at the front of the animal that resembles a true mouth. When the animal feeds, it pumps blood into the proboscis, inflating it and pushing it out through the opening to grasp the gastropod's prey."
"in the digestive system is to store feces that will be emptied into the rectum. It is retroperitoneal in two-thirds of humans. In the other third, it has a (usually short) mesentery. The arterial supply comes via the left colic artery. The descending colon is also called the ""distal gut"", as it is further along the gastrointestinal tract than the proximal gut. Gut flora are very dense in this region. The sigmoid colon is the part of the large intestine after the descending colon and before the rectum. The name ""sigmoid"" means S-shaped (see sigmoid; cf. sigmoid sinus). The walls"
"the colon or large intestine. Water is absorbed here and the remaining waste matter is stored prior to defecation. Most of the digestion of food takes place in the small intestine. A major digestive organ is the stomach. Within its mucosa are millions of embedded gastric glands. Their secretions are vital to the functioning of the organ. There are many specialised cells of the GI tract. These include the various cells of the gastric glands, taste cells, pancreatic duct cells, enterocytes and microfold cells. Some parts of the digestive system are also part of the excretory system, including the large"
"central cavity of the sac-like body. This cavity has only one opening to the outside which, in most cnidarians, is surrounded by tentacles for capturing prey. Gastrovascular cavity The gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Cnidaria (including jellyfish and corals) and Platyhelminthes (flatworms). The cavity may be extensively branched into a system of canals. In cnidarians, the gastrovascular system is also known as the coelenteron, and is commonly known as a ""blind gut"" or ""blind sac"", since food enters and waste exits through the same orifice. The radially symmetrical cnidarians"
"The duodenum is the first and shortest section of the small intestine. It is a hollow, jointed C-shaped tube connecting the stomach to the jejunum. It starts at the duodenal bulb and ends at the suspensory muscle of duodenum. The attachment of the suspensory muscle to the diaphragm is thought to help the passage of food by making a wider angle at its attachment. Most food digestion takes place in the small intestine. Segmentation contractions act to mix and move the chyme more slowly in the small intestine allowing more time for absorption (and these continue in the large intestine)."
"Gastrointestinal tract The gastrointestinal tract (digestive tract, digestional tract, GI tract, GIT, gut, or alimentary canal) is an organ system within humans and other animals which takes in food, digests it to extract and absorb energy and nutrients, and expels the remaining waste as feces. The mouth, esophagus, stomach and intestines are part of the gastrointestinal tract. ""Gastrointestinal"" is an adjective meaning of or pertaining to the stomach and intestines. A tract is a collection of related anatomic structures or a series of connected body organs. All bilaterians have a gastrointestinal tract, also called a gut or an alimentary canal."
"proteins, lipids, and vitamins) into the bloodstream. There are three major divisions: The large intestine also called the colon, consists of the cecum, rectum, and anal canal. It also includes the appendix, which is attached to the cecum. The colon is further divided into: The main function of the large intestine is to absorb water. The area of the large intestinal mucosa of an adult human is about 2 m. The gut is an endoderm-derived structure. At approximately the sixteenth day of human development, the embryo begins to fold ventrally (with the embryo's ventral surface becoming concave) in two directions:"
"of digestion are the oral cavity, the stomach, and the small intestine. Digestive enzymes are secreted by different exocrine glands including: Complex food substances that are taken by animals and humans must be broken down into simple, soluble, and diffusible substances before they can be absorbed. In the oral cavity, salivary glands secrete an array of enzymes and substances that aid in digestion and also disinfection. They include the following: Of note is the diversity of the salivary glands. There are two types of salivary glands: The enzymes that are secreted in the stomach are ""gastric enzymes"". The stomach plays"
"to be a single structure, deriving from the duodenojejunal flexure and extending to the distal mesorectum layer. The mesentery was then classified as an organ, enabling innovations in the fields of colon and rectum surgery and in sciences related to anatomy and development. The mesentery of the small intestine arises from the root of the mesentery (or mesenteric root) and is the part connected with the structures in front of the vertebral column. The root is narrow, about 15 cm long, 20 cm in width, and is directed obliquely from the duodenojejunal flexure at the left side of the second"
"Appendix (anatomy) The appendix (or vermiform appendix; also cecal [or caecal] appendix; vermix; or vermiform process) is a finger-like, blind-ended tube connected to the cecum, from which it develops in the embryo. The cecum is a pouchlike structure of the colon, located at the junction of the small and the large intestines. The term ""vermiform"" comes from Latin and means ""worm-shaped."" The appendix has been called a vestigial organ. The human appendix averages 9 cm in length but can range from 2 to 20 cm. The diameter of the appendix is usually between 7 and 8 mm. The longest appendix"
"be abnormally dilated when the diameter exceeds 3 cm. On CT scans, a diameter of over 2.5 cm is considered abnormally dilated. The surface area of the human small intestinal mucosa, due to enlargement caused by folds, villi and microvilli, averages 30 square meters. The small intestine is divided into three structural parts. The jejunum and ileum are suspended in the abdominal cavity by mesentery. The mesentery is part of the peritoneum. Arteries, veins, lymph vessels and nerves travel within the mesentery. The small intestine receives a blood supply from the coeliac trunk and the superior mesenteric artery. These are"
"The digestive system consists of the mouth including the tongue and teeth, esophagus, stomach, (gastrointestinal tract, small and large intestines, and rectum), as well as the liver, pancreas, gallbladder, and salivary glands. It converts food into small, nutritional, non-toxic molecules for distribution and absorption into the body. The endocrine system consists of the principal endocrine glands: the pituitary, thyroid, adrenals, pancreas, parathyroids, and gonads, but nearly all organs and tissues produce specific endocrine hormones as well. The endocrine hormones serve as signals from one body system to another regarding an enormous array of conditions, and resulting in variety of changes"