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Hindgut
The hindgut (or epigaster) is the posterior ( caudal) part of the alimentary canal. In mammals, it includes the distal one third of the transverse colon and the splenic flexure, the descending colon, sigmoid colon and up to the ano-rectal junction. In zoology, the term ''hindgut'' refers also to the cecum and ascending colon. Structure Blood supply Arterial supply is by the inferior mesenteric artery, and venous drainage is to the portal venous system. Lymphatic drainage is to the chyle cistern. Nerve supply The hindgut is innervated via the inferior mesenteric plexus. Sympathetic innervation is from the lumbar splanchnic nerves (L1-L2), parasympathetic innervation is from S2-S4. Development Additional images File:Gray985.png, Abdominal part of digestive tube and its attachment to the primitive or common mesentery. Human embryo of six weeks. File:Gray1115.png, Tail end of human embryo twenty-five to twenty-nine days old. File:Illacme plenipes female with 170 segments a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hindgut Fermentation
Hindgut fermentation is a digestive process seen in monogastric herbivores (animals with a simple, single-chambered stomach). Cellulose is digested with the aid of symbiotic microbes including bacteria, archaea, and eukaryotes. The microbial fermentation occurs in the digestive organs that follow the small intestine: the cecum and large intestine. Examples of hindgut fermenters include proboscideans and large odd-toed ungulates such as horses and rhinos, as well as small animals such as rodents, rabbits and koalas. In contrast, foregut fermentation is the form of cellulose digestion seen in ruminants such as cattle which have a four-chambered stomach, as well as in sloths, macropodids, some monkeys, and one bird, the hoatzin.. Cecum Hindgut fermenters generally have a cecum and large intestine that are much larger and more complex than those of a foregut or midgut fermenter. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alimentary Canal
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascular system. The GI tract contains all the major organs of the digestive system, in humans and other animals, including the esophagus, stomach, and intestines. Food taken in through the mouth is digested to extract nutrients and absorb energy, and the waste expelled at the anus as feces. ''Gastrointestinal'' is an adjective meaning of or pertaining to the stomach and intestines. Most animals have a "through-gut" or complete digestive tract. Exceptions are more primitive ones: sponges have small pores ( ostia) throughout their body for digestion and a larger dorsal pore ( osculum) for excretion, comb jellies have both a ventral mouth and dorsal anal pores, while cnidarians and acoels have a single pore for both digestion and excretion. The huma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Large Intestine
The large intestine, also known as the large bowel, is the last part of the gastrointestinal tract and of the Digestion, digestive system in tetrapods. Water is absorbed here and the remaining waste material is stored in the rectum as feces before being removed by defecation. The Colon (anatomy), colon (progressing from the ascending colon to the transverse colon, transverse, the descending colon, descending and finally the sigmoid colon) is the longest portion of the large intestine, and the terms "large intestine" and "colon" are often used interchangeably, but 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 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 colon, ascending the abdomen, across t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumbar Splanchnic Nerves
The lumbar splanchnic nerves are splanchnic nerves that arise from the lumbar ganglia (the lumbar part of the sympathetic trunk) and travel to an adjacent plexus near the aorta. They originate from L1 and L2. Together with fibres from the aortic plexus, they form the superior hypogastric plexus. These nerves contain preganglionic sympathetic and general visceral afferent fibers. The site of synapse is found in the inferior mesenteric ganglion and the postsynaptic fibers innervate the smooth muscle and glands A gland is a Cell (biology), cell or an Organ (biology), organ in an animal's body that produces and secretes different substances that the organism needs, either into the bloodstream or into a body cavity or outer surface. A gland may also funct ... of the pelvic viscera and hindgut. References External links * Nerves {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Mesenteric Artery
In human anatomy, the inferior mesenteric artery (IMA) is the third main branch of the abdominal aorta and arises at the level of L3, supplying the large intestine from the distal transverse colon to the upper part of the anal canal. The regions supplied by the IMA are the descending colon, the sigmoid colon, and part of the rectum. Structure Origin The IMA arises from the anterior aspect of the abdominal aorta. Its origin is situated at the L3 vertebral level ( subcostal plane), below the origins of the two renal arteries, 3-4 cm above the aortic bifurcation, at the level of the umbilicus, and posterior to the inferior border of the horizontal (III) part of the duodenum. Branches Along its course, the IMA has the following branches: All these arterial branches further divide into arcades which then supply the colon at regular intervals. Relations The IMA is accompanied along its course by a similarly named vein, the inferior mesenteric vein, which drains into the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoology
Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and how they interact with their ecosystems. Zoology is one of the primary branches of biology. The term is derived from Ancient Greek , ('animal'), and , ('knowledge', 'study'). Although humans have always been interested in the natural history of the animals they saw around them, and used this knowledge to domesticate certain species, the formal study of zoology can be said to have originated with Aristotle. He viewed animals as living organisms, studied their structure and development, and considered their adaptations to their surroundings and the function of their parts. Modern zoology has its origins during the Renaissance and early modern period, with Carl Linnaeus, Antonie van Leeuwenhoek, Robert Hooke, Charles Darwin, Gregor Mendel a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illacme Plenipes
''Illacme plenipes'' is a siphonorhinid millipede found in the central region of the U.S. state of California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an .... It has up to 750 legs. One of three known species in the genus '' Illacme'', it was first seen in 1926, but was not rediscovered until 2005, almost 80 years after its discovery, by Paul Marek, then a Ph.D. student at East Carolina University. Description On average, ''I. plenipes'' have over 600 legs, twice the average for millipede species, with one recorded specimen having 750 legs. It had the most legs of any species known until '' Eumillipes persephone'' was described in 2021, which had 1306 legs. It is relatively small-bodied among millipedes. Females grow to just over 3 cm; males are slightly smaller and h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Mesenteric Plexus
The inferior mesenteric plexus is derived chiefly from the aortic plexus. It surrounds the inferior mesenteric artery, and divides into a number of secondary plexuses, which are distributed to all the parts supplied by the artery, viz., the left colic and sigmoid plexuses, which supply the descending and sigmoid parts of the colon; and the superior hemorrhoidal plexus, which supplies the rectum and joins in the pelvis with branches from the pelvic plexuses. Additional images File:Gray838.png, The right sympathetic chain and its connections with the thoracic, abdominal, and pelvic plexuses. File:Gray839.png, Diagram of efferent sympathetic nervous system. See also * Inferior mesenteric artery In human anatomy, the inferior mesenteric artery (IMA) is the third main branch of the abdominal aorta and arises at the level of L3, supplying the large intestine from the distal transverse colon to the upper part of the anal canal. The region ... * Superior mesenteric plexus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chyle Cistern
The cisterna chyli or receptaculum chyli (chy·li pronounced: ˈkī-ˌlī) is a dilated sac at the lower end of the thoracic duct in most mammals into which lymph from the intestinal trunk and two lumbar lymphatic trunks flow. It receives fatty chyle from the intestines and thus acts as a conduit for the lipid products of digestion. It is the most common drainage trunk of most of the body's lymphatics. The cisterna chyli is a retroperitoneal structure. Structure In humans, the cisterna chyli is located posterior to the abdominal aorta on the anterior aspect of the bodies of the first and second lumbar vertebrae (L1 and L2). There it forms the beginning of the primary lymph vessel, the thoracic duct, which transports lymph and chyle from the abdomen via the aortic opening of the diaphragm up to the junction of left subclavian vein and internal jugular veins. Other animals In dogs, the cisterna chyli is located to the left and often ventral to the aorta; in cats it is left ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portal Venous System
In the circulatory system of vertebrates, a portal venous system occurs when a capillary bed pools into another capillary bed through veins, without first going through the heart. Both capillary beds and the blood vessels that connect them are considered part of the portal venous system. Most capillary beds drain into venules and veins which then drain into the heart, not into another capillary bed. There are three portal systems, two venous: the hepatic portal system and the hypophyseal portal system; and one arterial (one capillary system between two arteries): the renal portal system. Unqualified, ''portal venous system'' usually refers to the hepatic portal system. For this reason, portal vein most commonly refers to the hepatic portal vein. The functional significance of such a system is that it transports products of one region directly to another region in relatively high concentrations. If the heart were involved in the blood circulation between those two regions, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascending Colon
In the anatomy of humans and homologous primates, the ascending colon is the part of the colon located between the cecum and the transverse colon. Characteristics and structure The ascending colon is smaller in calibre than the cecum from where it starts. It passes upward, opposite the colic valve, to the under surface of the right lobe of the liver, on the right of the gall-bladder, where it is lodged in a shallow depression, the colic impression; here it bends abruptly forward and to the left, forming the right colic flexure (hepatic) where it becomes the transverse colon. It is retained in contact with the posterior wall of the abdomen by the peritoneum, which covers its anterior surface and sides, its posterior surface being connected by loose areolar tissue with the iliacus, quadratus lumborum, aponeurotic origin of transversus abdominis, and with the front of the lower and lateral part of the right kidney. Sometimes the peritoneum completely invests it and f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cecum
The cecum ( caecum, ; plural ceca or caeca, ) is a pouch within the peritoneum that is considered to be the beginning of the large intestine. It is typically located on the right side of the body (the same side of the body as the appendix (anatomy), appendix, to which it is joined). The term stems from the Latin ''wikt:caecus, caecus'', meaning "blindness, blind". It receives chyme from the ileum, and connects to the ascending colon of the large intestine. It is separated from the ileum by the ileocecal valve (ICV), also called Bauhin's valve. It is also separated from the Large intestine#Structure, colon by the cecocolic junction. While the cecum is usually intraperitoneal, the ascending colon is Retroperitoneal space, retroperitoneal. In herbivores, the cecum stores food material where bacteria are able to break down the cellulose. In humans, the cecum is involved in absorption of Salt (chemistry), salts and Electrolyte, electrolytes and lubricates the solid waste that pas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
