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Caecum
The cecum or caecum 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, to which it is joined). The word cecum (, plural ceca ) stems from the Latin '' caecus'' meaning 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) or Bauhin's valve. It is also separated from the colon by the cecocolic junction. While the cecum is usually intraperitoneal, the ascending colon is 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 salts and electrolytes and lubricates the solid waste that passes into the large intestine. Structure Development The cecum and appendix are formed by the enlargement of the postarterial segment of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Midgut
The midgut is the portion of the embryo from which most of the intestines develop. After it bends around the superior mesenteric artery, it is called the "midgut loop". It comprises the portion of the alimentary canal from the end of the foregut at the opening of the bile duct to the hindgut, about two-thirds of the way through the transverse colon. In the embryo During development, the human midgut undergoes a rapid phase of growth in which the loop of midgut herniates outside of the abdominal cavity of the fetus and protrudes into the umbilical cord. This herniation is physiological (occurs normally). Later in development, the fetus's body catches up in size relative to the midgut and creates adequate room in the abdominal cavity for the entirety of the midgut to reside. The midgut loops slip back out of the umbilical cord and the physiological hernia ceases to exist. This change coincides with the termination of the yolk sac and the counterclockwise rotation of the two limbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissection
Dissection (from Latin ' "to cut to pieces"; also called anatomization) is the dismembering of the body of a deceased animal or plant to study its anatomical structure. Autopsy is used in pathology and forensic medicine to determine the cause of death in humans. Less extensive dissection of plants and smaller animals preserved in a formaldehyde solution is typically carried out or demonstrated in biology and natural science classes in middle school and high school, while extensive dissections of cadavers of adults and children, both fresh and preserved are carried out by medical students in medical schools as a part of the teaching in subjects such as anatomy, pathology and forensic medicine. Consequently, dissection is typically conducted in a morgue or in an anatomy lab. Dissection has been used for centuries to explore anatomy. Objections to the use of cadavers have led to the use of alternatives including virtual dissection of computer models. Overview Plant and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaerobe
An anaerobic organism or anaerobe is any organism that does not require molecular oxygen for growth. It may react negatively or even die if free oxygen is present. In contrast, an aerobic organism (aerobe) is an organism that requires an oxygenated environment. Anaerobes may be unicellular (e.g. protozoans, bacteria) or multicellular. Most fungi are obligate aerobes, requiring oxygen to survive. However, some species, such as the Chytridiomycota that reside in the rumen of cattle, are obligate anaerobes; for these species, anaerobic respiration is used because oxygen will disrupt their metabolism or kill them. Deep waters of the ocean are a common anoxic environment. First observation In his letter of 14 June 1680 to The Royal Society, Antonie van Leeuwenhoek described an experiment he carried out by filling two identical glass tubes about halfway with crushed pepper powder, to which some clean rain water was added. Van Leeuwenhoek sealed one of the glass tubes using a flame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutropenic Enterocolitis
Neutropenic enterocolitis is inflammation of the cecum (part of the large intestine) that may be associated with infection. It is particularly associated with neutropenia, a low level of neutrophil granulocytes (the most common form of white blood cells) in the blood. Signs and symptoms Signs and symptoms of typhlitis may include diarrhea, a distended abdomen, fever, chills, nausea, vomiting, and abdominal pain or tenderness. Cause The condition is usually caused by Gram-positive enteric commensal bacteria of the gut (gut flora). ''Clostridium difficile'' is a species of Gram-positive bacteria that commonly causes severe diarrhea and other intestinal diseases when competing bacteria are wiped out by antibiotics, causing pseudomembranous colitis, whereas Clostridium septicum is responsible for most cases of neutropenic enterocolitis. Typhlitis most commonly occurs in immunocompromised patients, such as those undergoing chemotherapy, patients with AIDS, kidney transplant pati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Appendiceal Carcinoid Tumor
The appendix (or vermiform appendix; also cecal r caecalappendix; 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 pouch-like structure of the large intestine, located at the junction of the small and the large intestines. The term "vermiform" comes from Latin and means "worm-shaped". The appendix was once considered a vestigial organ, but this view has changed since the early 2000s. Research suggests that the appendix may serve an important purpose. In particular, it may serve as a reservoir for beneficial gut bacteria. Structure The human appendix averages in length but can range from . The diameter of the appendix is , and more than is considered a thickened or inflamed appendix. The longest appendix ever removed was long. The appendix is usually located in the lower right quadrant of the abdomen, near the right hip bone. The base of the appendix is located beneath the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcinoid Tumor
A carcinoid (also carcinoid tumor) is a slow-growing type of neuroendocrine tumor originating in the cells of the neuroendocrine system. In some cases, metastasis may occur. Carcinoid tumors of the midgut ( jejunum, ileum, appendix, and cecum) are associated with carcinoid syndrome. Carcinoid tumors are the most common malignant tumor of the appendix, but they are most commonly associated with the small intestine, and they can also be found in the rectum and stomach. They are known to grow in the liver, but this finding is usually a manifestation of metastatic disease from a primary carcinoid occurring elsewhere in the body. They have a very slow growth rate compared to most malignant tumors. The median age at diagnosis for all patients with neuroendocrine tumors is 63 years. Signs and symptoms While most carcinoids are asymptomatic through the natural life and are discovered only upon surgery for unrelated reasons (so-called ''coincidental carcinoids''), all carcinoids are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transverse Colon
In human anatomy, the transverse colon is the longest and most movable part of the colon. Anatomical position It crosses the abdomen from the ascending colon at the right colic flexure (hepatic flexure) with a downward convexity to the descending colon where it curves sharply on itself beneath the lower end of the spleen forming the left colic flexure (splenic flexure). In its course, it describes an arch, the concavity of which is directed backward and a little upward. Toward its splenic end there is often an abrupt U-shaped curve which may descend lower than the main curve. It is almost completely invested by the peritoneum, and is connected to the inferior border of the pancreas by a large and wide duplicature of that membrane, the transverse mesocolon. It is in relation, by its upper surface, with the liver and gall-bladder, the greater curvature of the stomach, and the lower end of the spleen; by its under surface, with the small intestine; by its anterior surface, wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Descending Colon
In the anatomy of humans and homologous primates, the descending colon is the part of the colon extending from the left colic flexure to the level of the iliac crest (whereupon it transitions into the sigmoid colon). The function of the descending colon in the digestive system is to store the remains of digested food that will be emptied into the rectum. The descending colon is on the left side of the body (barring any malformations). The term left colon is hypernymous to ''descending colon'' in precise use; many casual mentions of the left colon chiefly concern the descending colon. Structure The descending colon extends from the left colic flexure at the upper left part of the abdomen inferior-ward through the left hypochondrium and lumbar regions, along the outer border of the left kidney, ending at the level of the iliac crest at the lower left part of the abdomen, being contunued thenceforth as the sigmoid colon. It usually retroperitoneal (being lined by peritoneu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigmoid Colon
The sigmoid colon (or pelvic colon) is the part of the large intestine that is closest to the rectum and anus. It forms a loop that averages about in length. The loop is typically shaped like a Greek letter sigma (ς) or Latin letter S (thus ''sigma'' + '' -oid''). This part of the colon normally lies within the pelvis, but due to its freedom of movement it is liable to be displaced into the abdominal cavity. Structure The sigmoid colon begins at the superior aperture of the lesser pelvis, where it is continuous with the iliac colon, and passes transversely across the front of the sacrum to the right side of the pelvis. It then curves on itself and turns toward the left to reach the middle line at the level of the third piece of the sacrum, where it bends downward and ends in the rectum. Its function is to expel solid and gaseous waste from the gastrointestinal tract. The curving path it takes toward the anus allows it to store gas in the superior arched portion, enabling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rectum
The rectum is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. The adult human rectum is about long, and begins at the rectosigmoid junction (the end of the sigmoid colon) at the level of the third sacral vertebra or the sacral promontory depending upon what definition is used. Its diameter is similar to that of the sigmoid colon at its commencement, but it is dilated near its termination, forming the rectal ampulla. It terminates at the level of the anorectal ring (the level of the puborectalis sling) or the dentate line, again depending upon which definition is used. In humans, the rectum is followed by the anal canal which is about long, before the gastrointestinal tract terminates at the anal verge. The word rectum comes from the Latin '' rectum intestinum'', meaning ''straight intestine''. Structure The rectum is a part of the lower gastrointestinal tract. The rectum is a continuation of the sigmoi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Anatomy
The human body is the structure of a human being. It is composed of many different types of cells that together create tissues and subsequently organ systems. They ensure homeostasis and the viability of the human body. It comprises a head, hair, neck, trunk (which includes the thorax and abdomen), arms and hands, legs and feet. The study of the human body involves anatomy, physiology, histology and embryology. The body varies anatomically in known ways. Physiology focuses on the systems and organs of the human body and their functions. Many systems and mechanisms interact in order to maintain homeostasis, with safe levels of substances such as sugar and oxygen in the blood. The body is studied by health professionals, physiologists, anatomists, and by artists to assist them in their work. Composition The human body is composed of elements including hydrogen, oxygen, carbon, calcium and phosphorus. These elements reside in trillions of cells and non- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastrointestinal Tract
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 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 human gastrointestinal tract consists of the esophagus, stomach, and intestines, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
