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Digestion
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For the industrial process, see anaerobic digestion. For the treatment of precipitates in analytical chemistry, see Precipitation (chemistry) § Digestion.
Digestive system
Details
Latin
systema digestorium
Anatomical terminology
[edit on Wikidata]
Digestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into the blood stream. Digestion is a form of catabolism that is often divided into two processes based on how food is broken down: mechanical and chemical digestion. The term mechanical digestion refers to the physical breakdown of large pieces of food into smaller pieces which can subsequently be accessed by digestive enzymes. In chemical digestion, enzymes break down food into the small molecules the body can use.
In the human digestive system, food enters the mouth and mechanical digestion of the food starts by the action of mastication (chewing), a form of mechanical digestion, and the wetting contact of saliva. Saliva, a liquid secreted by the salivary glands, contains salivary amylase, an enzyme which starts the digestion of starch in the food; the saliva also contains mucus, which lubricates the food, and hydrogen carbonate, which provides the ideal conditions of pH (alkaline) for amylase to work. After undergoing mastication and starch digestion, the food will be in the form of a small, round slurry mass called a bolus. It will then travel down the esophagus and into the stomach by the action of peristalsis. Gastric juice in the stomach starts protein digestion. Gastric juice mainly contains hydrochloric acid and pepsin. As these two chemicals may damage the stomach wall, mucus is secreted by the stomach, providing a slimy layer that acts as a shield against the damaging effects of the chemicals. At the same time protein digestion is occurring, mechanical mixing occurs by peristalsis, which is waves of muscular contractions that move along the stomach wall. This allows the mass of food to further mix with the digestive enzymes.
After some time (typically 1–2 hours in humans, 4–6 hours in dogs, 3–4 hours in house cats),[citation needed] the resulting thick liquid is called chyme. When the pyloric sphincter valve opens, chyme enters the duodenum where it mixes with digestive enzymes from the pancreas and bile juice from the liver and then passes through the small intestine, in which digestion continues. When the chyme is fully digested, it is absorbed into the blood. 95% of absorption of nutrients occurs in the small intestine. Water and minerals are reabsorbed back into the blood in the colon (large intestine) where the pH is slightly acidic about 5.6 ~ 6.9. Some vitamins, such as biotin and vitamin K (K2MK7) produced by bacteria in the colon are also absorbed into the blood in the colon. Waste material is eliminated from the rectum during defecation.[1]
Contents
[hide]
1 Digestive system
1.1 Secretion systems
1.1.1 Channel transport system
1.1.2 Molecular syringe
1.1.3 Conjugation machinery
1.1.4 Release of outer membrane vesicles
1.2 Gastrovascular cavity
1.3 Phagosome
1.4 Specialised organs and behaviours
1.4.1 Beaks
1.4.2 Tongue
1.4.3 Teeth
1.4.4 Crop
1.4.5 Abomasum
1.4.6 Specialised behaviours
1.5 In earthworms
2 Overview of vertebrate digestion
3 Human digestion process
3.1 Neural and biochemical control mechanisms
4 Breakdown into nutrients
4.1 Protein digestion
4.2 Fat digestion
4.3 Carbohydrate digestion
4.4 DNA and RNA digestion
5 Non-destructive digestion
6 Digestive hormones
7 Significance of pH
8 See also
9 References
10 External links
Digestive system
Digestive systems take many forms. There is a fundamental distinction between internal and external digestion. External digestion developed earlier in evolutionary history, and most fungi still rely on it.[2] In this process, enzymes are secreted into the environment surrounding the organism, where they break down an organic material, and some of the products diffuse back to the organism. Animals have a tube (gastrointestinal tract) in which internal digestion occurs, which is more efficient because more of the broken down products can be captured, and the internal chemical environment can be more efficiently controlled.[3]
Some organisms, including nearly all spiders, simply secrete biotoxins and digestive chemicals (e.g., enzymes) into the extracellular environment prior to ingestion of the consequent "soup". In others, once potential nutrients or food is inside the organism, digestion can be conducted to a vesicle or a sac-like structure, through a tube, or through several specialized organs aimed at making the absorption of nutrients more efficient.
Schematic drawing of bacterial conjugation. 1- Donor cell produces pilus. 2- Pilus attaches to recipient cell, bringing the two cells together. 3- The mobile plasmid is nicked and a single strand of DNA is transferred to the recipient cell. 4- Both cells recircularize their plasmids, synthesize second strands, and reproduce pili; both cells are now viable donors.
Secretion systems
Main article: Secretion § Secretion in Gram negative bacteria
Bacteria use several systems to obtain nutrients from other organisms in the environments.
Channel transport system
In a channel transupport system, several proteins form a contiguous channel traversing the inner and outer membranes of the bacteria. It is a simple system, which consists of only three protein subunits: the ABC protein, membrane fusion protein (MFP), and outer membrane protein (OMP)[specify]. This secretion system transports various molecules, from ions, drugs, to proteins of various sizes (20 – 900 kDa). The molecules secreted vary in size from the small Escherichia coli peptide colicin V, (10 kDa) to the Pseudomonas fluorescens cell adhesion protein LapA of 900 kDa.[4]
Molecular syringe
A type III secretion system means that a molecular syringe is used through which a bacterium (e.g. certain types of Salmonella, Shigella, Yersinia) can inject nutrients into protist cells. One such mechanism was first discovered in Y. pestis and showed that toxins could be injected directly from the bacterial cytoplasm into the cytoplasm of its host's cells rather than simply be secreted into the extracellular medium.[5]
Conjugation machinery
The conjugation machinery of some bacteria (and archaeal flagella) is capable of transporting both DNA and proteins. It was discovered in Agrobacterium tumefaciens, which uses this system to introduce the Ti plasmid and proteins into the host, which develops the crown gall (tumor).[6] The VirB complex of Agrobacterium tumefaciens is the prototypic system.[7]
The nitrogen fixing Rhizobia are an interesting case, wherein conjugative elements naturally engage in inter-kingdom conjugation. Such elements as the Agrobacterium Ti or Ri plasmids contain elements that can transfer to plant cells. Transferred genes enter the plant cell nucleus and effectively transform the plant cells into factories for the production of opines, which the bacteria use as carbon and energy sources. Infected plant cells form crown gall or root tumors. The Ti and Ri plasmids are thus endosymbionts of the bacteria, which are in turn endosymbionts (or parasites) of the infected plant.
The Ti and Ri plasmids are themselves conjugative. Ti and Ri transfer between bacteria uses an independent system (the tra, or transfer, operon) from that for inter-kingdom transfer (the vir, or virulence, operon). Such transfer creates virulent strains from previously avirulent Agrobacteria.
Release of outer membrane vesicles
In addition to the use of the multiprotein complexes listed above, Gram-negative bacteria possess another method for release of material: the formation of outer membrane vesicles.[8][9] Portions of the outer membrane pinch off, forming spherical structures made of a lipid bilayer enclosing periplasmic materials. Vesicles from a number of bacterial species have been found to contain virulence factors, some have immunomodulatory effects, and some can directly adhere to and intoxicate host cells. While release of vesicles has been demonstrated as a general response to stress conditions, the process of loading cargo proteins seems to be selective.[10]
Venus Flytrap (Dionaea muscipula) leaf
Gastrovascular cavity
The gastrovascular cavity functions as a stomach in both digestion and the distribution of nutrients to all parts of the body. Extracellular digestion takes place within this central cavity, which is lined with the gastrodermis, the internal layer of epithelium. This cavity has only one opening to the outside that functions as both a mouth and an anus: waste and undigested matter is excreted through the mouth/anus, which can be described as an incomplete gut.
In a plant such as the Venus Flytrap that can make its own food through photosynthesis, it does not eat and digest its prey for the traditional objectives of harvesting energy and carbon, but mines prey primarily for essential nutrients (nitrogen and phosphorus in particular) that are in short supply in its boggy, acidic habitat.[11]
Trophozoites of Entamoeba histolytica with ingested erythrocytes
Phagosome
A phagosome is a vacuole formed around a particle absorbed by phagocytosis. The vacuole is formed by the fusion of the cell membrane around the particle. A phagosome is a cellular compartment in which pathogenic microorganisms can be killed and digested. Phagosomes fuse with lysosomes in their maturation process, forming phagolysosomes. In humans, Entamoeba histolytica can phagocytose red blood cells.[12]
Specialised organs and behaviours
To aid in the digestion of their food animals evolved organs such as beaks, tongues, teeth, a crop, gizzard, and others.
A Catalina Macaw's seed-shearing beak
Squid beak with ruler for size comparison
Beaks
Birds have bony beaks that are specialised according to the bird's ecological niche. For example, macaws primarily eat seeds, nuts, and fruit, using their impressive beaks to open even the toughest seed. First they scratch a thin line with the sharp point of the beak, then they shear the seed open with the sides of the beak.
The mouth of the squid is equipped with a sharp horny beak mainly made of cross-linked proteins. It is used to kill and tear prey into manageable pieces. The beak is very robust, but does not contain any minerals, unlike the teeth and jaws of many other organisms, including marine species.[13] The beak is the only indigestible part of the squid.
Tongue
Main article: Tongue
The tongue is skeletal muscle on the floor of the mouth that manipulates food for chewing (mastication) and swallowing (deglutition). It is sensitive and kept moist by saliva. The underside of the tongue is covered with a smooth mucous membrane. The tongue also has a touch sense for locating and positioning food particles that require further chewing. The tongue is utilized to roll food particles into a bolus before being transported down the esophagus through peristalsis.
The sublingual region underneath the front of the tongue is a location where the oral mucosa is very thin, and underlain by a plexus of veins. This is an ideal location for introducing certain medications to the body. The sublingual route takes advantage of the highly vascular quality of the oral cavity, and allows for the speedy application of medication into the cardiovascular system, bypassing the gastrointestinal tract.
Teeth
Main article: Teeth
Teeth (singular tooth) are small whitish structures found in the jaws (or mouths) of many vertebrates that are used to tear, scrape, milk and chew food. Teeth are not made of bone, but rather of tissues of varying density and hardness, such as enamel, dentine and cementum. Human teeth have a blood and nerve supply which enables proprioception. This is the ability of sensation when chewing, for example if we were to bite into something too hard for our teeth, such as a chipped plate mixed in food, our teeth send a message to our brain and we realise that it cannot be chewed, so we stop trying.
The shapes, sizes and numbers of types of animals' teeth are related to their diets. For example, herbivores have a number of molars which are used to grind plant matter, which is difficult to digest. Carnivores have canine teeth which are used to kill and tear meat.
Crop
A crop, or croup, is a thin-walled expanded portion of the alimentary tract used for the storage of food prior to digestion. In some birds it is an expanded, muscular pouch near the gullet or throat. In adult doves and pigeons, the crop can produce crop milk to feed newly hatched birds.[14]
Certain insects may have a crop or enlarged esophagus.
Rough illustration of a ruminant digestive system
Abomasum
Main article: Abomasum
Herbivores have evolved cecums (or an abomasum in the case of ruminants). Ruminants have a fore-stomach with four chambers. These are the rumen, reticulum, omasum, and abomasum. In the first two chambers, the rumen and the reticulum, the food is mixed with saliva and separates into layers of solid and liquid material. Solids clump together to form the cud (or bolus). The cud is then regurgitated, chewed slowly to completely mix it with saliva and to break down the particle size.
Fibre, especially cellulose and hemi-cellulose, is primarily broken down into the volatile fatty acids, acetic acid, propionic acid and butyric acid in these chambers (the reticulo-rumen) by microbes: (bacteria, protozoa, and fungi). In the omasum, water and many of the inorganic mineral elements are absorbed into the blood stream.
The abomasum is the fourth and final stomach compartment in ruminants. It is a close equivalent of a monogastric stomach (e.g., those in humans or pigs), and digesta is processed here in much the same way. It serves primarily as a site for acid hydrolysis of microbial and dietary protein, preparing these protein sources for further digestion and absorption in the small intestine. Digesta is finally moved into the small intestine, where the digestion and absorption of nutrients occurs. Microbes produced in the reticulo-rumen are also digested in the small intestine.
A flesh fly "blowing a bubble", possibly to concentrate its food by evaporating water
Specialised behaviours
Regurgitation has been mentioned above under abomasum and crop, referring to crop milk, a secretion from the lining of the crop of pigeons and doves with which the parents feed their young by regurgitation.[15]
Many sharks have the ability to turn their stomachs inside out and evert it out of their mouths in order to get rid of unwanted contents (perhaps developed as a way to reduce exposure to toxins).
Other animals, such as rabbits and rodents, practise coprophagia behaviours – eating specialised faeces in order to re-digest food, especially in the case of roughage. Capybara, rabbits, hamsters and other related species do not have a complex digestive system as do, for example, ruminants. Instead they extract more nutrition from grass by giving their food a second pass through the gut. Soft faecal pellets of partially digested food are excreted and generally consumed immediately. They also produce normal droppings, which are not eaten.
Young elephants, pandas, koalas, and hippos eat the faeces of their mother, probably to obtain the bacteria required to properly digest vegetation. When they are born, their intestines do not contain these bacteria (they are completely sterile). Without them, they would be unable to get any nutritional value from many plant components.
In earthworms
An earthworm's digestive system consists of a mouth, pharynx, esophagus, crop, gizzard, and intestine. The mouth is surrounded by strong lips, which act like a hand to grab pieces of dead grass, leaves, and weeds, with bits of soil to help chew. The lips break the food down into smaller pieces. In the pharynx, the food is lubricated by mucus secretions for easier passage. The esophagus adds calcium carbonate to neutralize the acids formed by food matter decay. Temporary storage occurs in the crop where food and calcium carbonate are mixed. The powerful muscles of the gizzard churn and mix the mass of food and dirt. When the churning is complete, the glands in the walls of the gizzard add enzymes to the thick paste, which helps chemically breakdown the organic matter. By peristalsis, the mixture is sent to the intestine where friendly bacteria continue chemical breakdown. This releases carbohydrates, protein, fat, and various vitamins and minerals for absorption into the body.
Overview of vertebrate digestion
In most vertebrates, digestion is a multistage process in the digestive system, starting from ingestion of raw materials, most often other organisms. Ingestion usually involves some type of mechanical and chemical processing. Digestion is separated into four steps:
Ingestion: placing food into the mouth (entry of food in the digestive system),
Mechanical and chemical breakdown: mastication and the mixing of the resulting bolus with water, acids, bile and enzymes in the stomach and intestine to break down complex molecules into simple structures,
Absorption: of nutrients from the digestive system to the circulatory and lymphatic capillaries through osmosis, active transport, and diffusion, and
Egestion (Excretion): Removal of undigested materials from the digestive tract through defecation.
Underlying the process is muscle movement throughout the system through swallowing and peristalsis. Each step in digestion requires energy, and thus imposes an "overhead charge" on the energy made available from absorbed substances. Differences in that overhead cost are important influences on lifestyle, behavior, and even physical structures. Examples may be seen in humans, who differ considerably from other hominids (lack of hair, smaller jaws and musculature, different dentition, length of intestines, cooking, etc.).
The major part of digestion takes place in the small intestine. The large intestine primarily serves as a site for fermentation of indigestible matter by gut bacteria and for resorption of water from digests before excretion.
In mammals, preparation for digestion begins with the cephalic phase in which saliva is produced in the mouth and digestive enzymes are produced in the stomach. Mechanical and chemical digestion begin in the mouth where food is chewed, and mixed with saliva to begin enzymatic processing of starches. The stomach continues to break food down mechanically and chemically through churning and mixing with both acids and enzymes. Absorption occurs in the stomach and gastrointestinal tract, and the process finishes with defecation.[1]
Human digestion process
Main article: Human digestive system
Upper and lower human gastrointestinal tract
The human gastrointestinal tract is around 9 meters long. Food digestion physiology varies between individuals and upon other factors such as the characteristics of the food and size of the meal, and the process of digestion normally takes between 24 and 72 hours.[16]
Digestion begins in the mouth with the secretion of saliva and its digestive enzymes. Food is formed into a bolus by the mechanical mastication and swallowed into the esophagus from where it enters the stomach through the action of peristalsis. Gastric juice contains hydrochloric acid and pepsin which would damage the walls of the stomach and mucus is secreted for protection. In the stomach further release of enzymes break down the food further and this is combined with the churning action of the stomach. The partially digested food enters the duodenum as a thick semi-liquid chyme. In the small intestine, the larger part of digestion takes place and this is helped by the secretions of bile, pancreatic juice and intestinal juice. The intestinal walls are lined with villi, and their epithelial cells is covered with numerous microvilli to improve the absorption of nutrients by increasing the surface area of the intestine.
In the large intestine the passage of food is slower to enable fermentation by the gut flora to take place. Here water is absorbed and waste material stored as feces to be removed by defecation via the anal canal and anus.
Neural and biochemical control mechanisms
Different phases of digestion take place including: the cephalic phase, gastric phase, and intestinal phase.
The cephalic phase occurs at the sight, thought and smell of food, which stimulate the cerebral cortex. Taste and smell stimuli are sent to the hypothalamus and medulla oblongata. After this it is routed through the vagus nerve and release of acetylcholine. Gastric secretion at this phase rises to 40% of maximum rate. Acidity in the stomach is not buffered by food at this point and thus acts to inhibit parietal (secretes acid) and G cell (secretes gastrin) activity via D cell secretion of somatostatin.
The gastric phase takes 3 to 4 hours. It is stimulated by distension of the stomach, presence of food in stomach and decrease in pH. Distention activates long and myenteric reflexes. This activates the release of acetylcholine, which stimulates the release of more gastric juices. As protein enters the stomach, it binds to hydrogen ions, which raises the pH of the stomach. Inhibition of gastrin and gastric acid secretion is lifted. This triggers G cells to release gastrin, which in turn stimulates parietal cells to secrete gastric acid. Gastric acid is about 0.5% hydrochloric acid (HCl), which lowers the pH to the desired pH of 1-3. Acid release is also triggered by acetylcholine and histamine.
The intestinal phase has two parts, the excitatory and the inhibitory. Partially digested food fills the duodenum. This triggers intestinal gastrin to be released. Enterogastric reflex inhibits vagal nuclei, activating sympathetic fibers causing the pyloric sphincter to tighten to prevent more food from entering, and inhibits local reflexes.
Breakdown into nutrients
This section needs expansion with: digestion of other substances. You can help by adding to it. (August 2011)
Protein digestion
Protein digestion occurs in the stomach and duodenum in which 3 main enzymes, pepsin secreted by the stomach and trypsin and chymotrypsin secreted by the pancreas, break down food proteins into polypeptides that are then broken down by various exopeptidases and dipeptidases into amino acids. The digestive enzymes however are mostly secreted as their inactive precursors, the zymogens. For example, trypsin is secreted by pancreas in the form of trypsinogen, which is activated in the duodenum by enterokinase to form trypsin. Trypsin then cleaves proteins to smaller polypeptides.
Fat digestion
Main article: Fatty acid metabolism § Dietary sources of fatty acids, their digestion, absorption, transport in the blood and storage
Digestion of some fats can begin in the mouth where lingual lipase breaks down some short chain lipids into diglycerides. However fats are mainly digested in the small intestine.[17] The presence of fat in the small intestine produces hormones that stimulate the release of pancreatic lipase from the pancreas and bile from the liver which helps in the emulsification of fats for absorption of fatty acids.[17] Complete digestion of one molecule of fat (a triglyceride) results a mixture of fatty acids, mono- and di-glycerides, as well as some undigested triglycerides, but no free glycerol molecules.[17]
Carbohydrate digestion
In humans, dietary starches are composed of glucose units arranged in long chains called amylose, a polysaccharide. During digestion, bonds between glucose molecules are broken by salivary and pancreatic amylase, resulting in progressively smaller chains of glucose. This results in simple sugars glucose and maltose (2 glucose molecules) that can be absorbed by the small intestine.
Lactase is an enzyme that breaks down the disaccharide lactose to its component parts, glucose and galactose. Glucose and galactose can be absorbed by the small intestine. Approximately 65 percent of the adult population produce only small amounts of lactase and are unable to eat unfermented milk-based foods. This is commonly known as lactose intolerance. Lactose intolerance varies widely by ethnic heritage; more than 90 percent of peoples of east Asian descent are lactose intolerant, in contrast to about 5 percent of people of northern European descent.[18]
Sucrase is an enzyme that breaks down the disaccharide sucrose, commonly known as table sugar, cane sugar, or beet sugar. Sucrose digestion yields the sugars fructose and glucose which are readily absorbed by the small intestine.
DNA and RNA digestion
DNA and RNA are broken down into mononucleotides by the nucleases deoxyribonuclease and ribonuclease (DNase and RNase) from the pancreas.
Non-destructive digestion
Some nutrients are complex molecules (for example vitamin B12) which would be destroyed if they were broken down into their functional groups. To digest vitamin B12 non-destructively, haptocorrin in saliva strongly binds and protects the B12 molecules from stomach acid as they enter the stomach and are cleaved from their protein complexes.[19]
After the B12-haptocorrin complexes pass from the stomach via the pylorus to the duodenum, pancreatic proteases cleave haptocorrin from the B12 molecules which rebind to intrinsic factor (IF). These B12-IF complexes travel to the ileum portion of the small intestine where cubilin receptors enable assimilation and circulation of B12-IF complexes in the blood.[20]
Digestive hormones
Action of the major digestive hormones
There are at least five hormones that aid and regulate the digestive system in mammals. There are variations across the vertebrates, as for instance in birds. Arrangements are complex and additional details are regularly discovered. For instance, more connections to metabolic control (largely the glucose-insulin system) have been uncovered in recent years.
Gastrin – is in the stomach and stimulates the gastric glands to secrete pepsinogen (an inactive form of the enzyme pepsin) and hydrochloric acid. Secretion of gastrin is stimulated by food arriving in stomach. The secretion is inhibited by low pH.
Secretin – is in the duodenum and signals the secretion of sodium bicarbonate in the pancreas and it stimulates the bile secretion in the liver. This hormone responds to the acidity of the chyme.
Cholecystokinin (CCK) – is in the duodenum and stimulates the release of digestive enzymes in the pancreas and stimulates the emptying of bile in the gall bladder. This hormone is secreted in response to fat in chyme.
Gastric inhibitory peptide (GIP) – is in the duodenum and decreases the stomach churning in turn slowing the emptying in the stomach. Another function is to induce insulin secretion.
Motilin – is in the duodenum and increases the migrating myoelectric complex component of gastrointestinal motility and stimulates the production of pepsin.
Significance of pH
Digestion is a complex process controlled by several factors. pH plays a crucial role in a normally functioning digestive tract. In the mouth, pharynx and esophagus, pH is typically about 6.8, very weakly acidic. Saliva controls pH in this region of the digestive tract. Salivary amylase is contained in saliva and starts the breakdown of carbohydrates into monosaccharides. Most digestive enzymes are sensitive to pH and will denature in a high or low pH environment.
The stomach's high acidity inhibits the breakdown of carbohydrates within it. This acidity confers two benefits: it denatures proteins for further digestion in the small intestines, and provides non-specific immunity, damaging or eliminating various pathogens.[citation needed]
In the small intestines, the duodenum provides critical pH balancing to activate digestive enzymes. The liver secretes bile into the duodenum to neutralize the acidic conditions from the stomach, and the pancreatic duct empties into the duodenum, adding bicarbonate to neutralize the acidic chyme, thus creating a neutral environment. The mucosal tissue of the small intestines is alkaline with a pH of about 8.5.[citation needed]
See also
Digestive system of gastropods
Digestive system of humpback whales
Erepsin
Gastroesophageal reflux disease
Discovery and development of proton pump inhibitors
References
^ Jump up to: a b Maton, Anthea; Jean Hopkins; Charles William McLaughlin; Susan Johnson; Maryanna Quon Warner; David LaHart; Jill D. Wright (1993). Human Biology and Health. Englewood Cliffs, New Jersey, USA: Prentice Hall. ISBN 0-13-981176-1. OCLC 32308337.
Jump up ^ Dusenbery, David B. (1996). “Life at Small Scale”, pp. 113-115. Scientific American Library, New York. ISBN 0-7167-5060-0.
Jump up ^ Dusenbery, David B. (2009). Living at Micro Scale, p. 280. Harvard University Press, Cambridge, Mass. ISBN 978-0-674-03116-6.
Jump up ^ Wooldridge K (editor) (2009). Bacterial Secreted Proteins: Secretory Mechanisms and Role in Pathogenesis. Caister Academic Press. ISBN 978-1-904455-42-4. CS1 maint: Extra text: authors list (link)
Jump up ^ Salyers, A. A. & Whitt, D. D. (2002). Bacterial Pathogenesis: A Molecular Approach, 2nd ed., Washington, D.C.: ASM Press. ISBN 1-55581-171-X
Jump up ^ Cascales E, Christie PJ (2003). "The versatile Type IV secretion systems". Nature Reviews Microbiology. 1 (2): 137–149. doi:10.1038/nrmicro753. PMC 3873781  . PMID 15035043.
Jump up ^ Christie PJ; Atmakuri K; Jabubowski S; Krishnamoorthy V; Cascales E. (2005). "Biogenesis, architecture, and function of bacterial Type IV secretion systems". Annu Rev Microbiol. 59: 451–485. doi:10.1146/annurev.micro.58.030603.123630. PMC 3872966  . PMID 16153176.
Jump up ^ Chatterjee, S. N.; Das, J (1967). "Electron microscopic observations on the excretion of cell-wall material by Vibrio cholerae". Journal of General Microbiology. 49 (1): 1–11. doi:10.1099/00221287-49-1-1. PMID 4168882.
Jump up ^ Kuehn, M. J.; Kesty, N. C. (2005). "Bacterial outer membrane vesicles and the host-pathogen interaction". Genes & Development. 19 (22): 2645–55. doi:10.1101/gad.1299905. PMID 16291643.
Jump up ^ McBroom, A. J.; Kuehn, M. J. (2007). "Release of outer membrane vesicles by Gram-negative bacteria is a novel envelope stress response". Molecular Microbiology. 63 (2): 545–558. doi:10.1111/j.1365-2958.2006.05522.x. PMC 1868505  . PMID 17163978.
Jump up ^ Leege, Lissa. "How does the Venus flytrap digest flies?". Scientific American. Retrieved 2008-08-20.
Jump up ^ Boettner, D. R.; Huston, C. D.; Linford, A. S.; Buss, S. N.; Houpt, E.; Sherman, N. E.; Petri, W. A. (2008). "Entamoeba histolytica Phagocytosis of Human Erythrocytes Involves PATMK, a Member of the Transmembrane Kinase Family". PLoS Pathogens. 4 (1): e8. doi:10.1371/journal.ppat.0040008. PMC 2211552  . PMID 18208324.
Jump up ^ Miserez, A; Li, Y; Waite, H; Zok, F (2007). "Jumbo squid beaks: Inspiration for design of robust organic composites". Acta Biomaterialia. 3 (1): 139–149. doi:10.1016/j.actbio.2006.09.004. PMID 17113369.
Jump up ^ Gordon John Larkman Ramel (2008-09-29). "The Alimentary Canal in Birds". Retrieved 2008-12-16.
Jump up ^ Levi, Wendell (1977). The Pigeon. Sumter, S.C.: Levi Publishing Co, Inc. ISBN 0-85390-013-2.
Jump up ^ Kong F, Singh RP (June 2008). "Disintegration of solid foods in human stomach". J. Food Sci. 73 (5): R67–80. doi:10.1111/j.1750-3841.2008.00766.x. PMID 18577009.
^ Jump up to: a b c Digestion of fats (triacylglycerols)
Jump up ^ "Genetics Home Reference". US National Library of Medicine. US National Institutes of Health. Retrieved 27 June 2015.
Jump up ^ Nexo E, Hoffmann-Lücke E (July 2011). "Holotranscobalamin, a marker of vitamin B-12 status: analytical aspects and clinical utility". Am. J. Clin. Nutr. 94 (1): 359S–365S. doi:10.3945/ajcn.111.013458. PMC 3127504  . PMID 21593496.
Jump up ^ Viola-Villegas N, Rabideau AE, Bartholomä M, Zubieta J, Doyle RP (August 2009). "Targeting the cubilin receptor through the vitamin B(12) uptake pathway: cytotoxicity and mechanistic insight through fluorescent Re(I) delivery". J. Med. Chem. 52 (16): 5253–61. doi:10.1021/jm900777v. PMID 19627091.
External links
Human Physiology – Digestion
NIH guide to digestive system
The Digestive System
How does the Digestive System Work?
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Digestive system
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text:
Walk of Punishment
From Wikipedia, the free encyclopedia
Jump to: navigation, search
"Walk of Punishment"
Game of Thrones episode
Jaime Lannister loses his hand.
Episode no.
Season 3
Episode 3
Directed by
David Benioff
Written by
David Benioff
D. B. Weiss
Featured music
Ramin Djawadi
Cinematography by
Matthew Jensen
Editing by
Katie Weiland
Original air date
April 14, 2013 (2013-04-14)
Running time
53 minutes
Guest appearance(s)
Ciarán Hinds as Mance Rayder
Robert Pugh as Craster
Ian McElhinney as Barristan Selmy
Gwendoline Christie as Brienne of Tarth
Mackenzie Crook as Orell
Paul Kaye as Thoros of Myr
Clive Russell as Brynden "Blackfish" Tully
Tobias Menzies as Edmure Tully
Kristofer Hivju as Tormund Giantsbane
Julian Glover as Grand Maester Pycelle
Iwan Rheon as Boy
Noah Taylor as Locke
Mark Stanley as Grenn
Ben Crompton as Edd Tollett
Luke Barnes as Rast
Burn Gorman as Karl
Hannah Murray as Gilly
Ben Hawkey as Hot Pie
Esmé Bianco as Ros
Daniel Portman as Podrick Payne
Philip McGinley as Anguy
Dan Hildebrand as Kraznys mo Nakloz
Nathalie Emmanuel as Missandei
Michael Shelford as Torturer
Clifford Barry as Greizhen mo Ullhor
Gary Lightbody as a Bolton soldier
Kylie Harris as Genna
Josephine Gillan as Marei
Pixie Le Knot as Kayla
Dean-Charles Chapman as Martyn Lannister
Episode chronology
← Previous
"Dark Wings, Dark Words" Next →
"And Now His Watch Is Ended"
Game of Thrones (season 3)
List of Game of Thrones episodes
"Walk of Punishment" is the third episode of the third season of HBO's fantasy television series Game of Thrones, and the 23rd episode of the series. Written by David Benioff and D. B. Weiss, and directed by Benioff, it aired on April 14, 2013.
The title of the episode alludes to a place called "The Walk of Punishment" in the series, a road where slaves are crucified and displayed as examples to the slaves who thought of disobeying their masters.
The episode received a nomination for a Primetime Emmy Award for Outstanding Costumes for a Series at the 65th Primetime Creative Arts Emmy Awards.
Contents
[hide]
1 Plot
1.1 In King's Landing
1.2 In the North
1.3 At Dragonstone
1.4 In Astapor
1.5 Beyond the Wall
1.6 At Riverrun
1.7 In the Riverlands
2 Production
2.1 Writing
2.2 Directing
2.3 Casting
2.4 Filming locations
2.5 Music
3 Reception
3.1 Ratings
3.2 Critical reception
4 References
5 External links
Plot[edit]
In King's Landing[edit]
Tywin Lannister calls a meeting of the Small Council. He demands knowledge of Jaime's location, which the spymaster, Lord Varys, is unable to provide. Tywin then announces plans to have Lord Petyr Baelish wed Lysa Arryn to deprive Robb Stark of more allies in the war. Tywin names his son Tyrion as Baelish's replacement as Master of Coin (treasurer), despite Tyrion's pointing out his lack of expertise. Later, while retrieving the ledgers for his new appointment, Lord Baelish advises Tyrion on the job. Tyrion then rewards his virgin squire Podrick Payne with the services of three prostitutes for saving his life in the Battle of the Blackwater; Tyrion is later surprised to discover that they refuse payment due to Podrick's skill in lovemaking. While going over the books, Tyrion discovers that as treasurer Baelish has borrowed millions in gold from Tywin, as well as tens of millions from the Iron Bank of Braavos. A debt to Tywin is a problem since, regardless of his familial relationship with the king, Tyrion fears he will not forgive the debt despite the crown's dire straits. However, he is more worried about the Iron Bank, since if they are not paid back in due time they may very well begin funding the Crown's enemies.
In the North[edit]
Theon Greyjoy is awakened by the cleaning boy, released from his bondage, given a horse, and told to ride east to his sister, Yara, at Deepwood Motte. After riding all night, Theon finds out that he is being pursued by his captors; he is soon caught and knocked off his horse. Moments before their leader attempts to rape him, Theon is saved by the cleaning boy, an expert bowman, who kills the soldiers and accompanies him onward.
At Dragonstone[edit]
Stannis Baratheon accuses Melisandre of trying to abandon him as she is heading to a ship bound for an unknown destination which she claims will be revealed to her by the Lord of Light. Stannis begs her to give him another son, but she says he does not have the strength. She informs him that her magic requires king's blood and that it will be necessary to acquire it from others who share Stannis' blood.
In Astapor[edit]
Ser Jorah Mormont and Ser Barristan Selmy offer Daenerys Targaryen their differing counsel over the choice of soldiers to use upon their return to Westeros. Ser Barristan would have them use free, loyal men, while Ser Jorah presses in favor of the Unsullied. Shortly afterwards, Daenerys declares to slaver Kraznys mo Nakloz that she wishes to purchase all 8,000 Unsullied and the boys still in training to become Unsullied. When Kraznys tells her she cannot afford them, as in their previous conversation, insulting her in Old Valyrian all the while, which insults the translator diplomatically omits. Daenerys offers one of her dragons, despite the counsel of both Jorah and Barristan. Kraznys demands all three dragons, then two, then simply the largest one, to which Daenerys finally agrees. Before leaving, Daenerys demands Kraznys's slave translator Missandei as a gift "for a bargain well struck," and departs with her.
Beyond the Wall[edit]
The wildling army, led by Mance Rayder arrives at the Fist of the First Men to find a field of decapitated horses arranged in shape of a whirl by the White Walkers. Jon Snow notes that there are no dead Night's Watch brothers amongst the horses, which Orell claims he had seen. Rayder tells Jon that the dead have become wights, and orders Tormund Giantsbane to take 20 men, along with Jon, and climb the Wall. Rayder then says he will light the biggest fire the North has seen to signal them to attack the Night's Watch. He stipulates that if Snow doesn't prove useful, he can be thrown off the Wall.
Arriving at Craster's Keep, the remaining Night's Watch brothers seek refuge under his roof. Threatened by the desperate brothers, Craster reluctantly allows them into his keep. After being ridiculed by Craster, Samwell Tarly leaves the keep and witnesses Gilly giving birth to a boy.
At Riverrun[edit]
Props from the episode: Jaime Lannister's severed hand, his shackles and Locke's cleaver.
Lord Hoster Tully is given a ship burial, attended by his family and bannermen. When his son, Edmure, is unable to set the boat ablaze despite three arrow shots, Hoster's brother, Brynden "the Blackfish" shoves Edmure out of the way and with one arrow sets the boat on fire, shaming Edmure in front of the group. Shortly after, while in conference with King Robb, Edmure is chastised for having disobeyed orders not to engage Ser Gregor Clegane. Later, Lady Catelyn Stark discusses her pain with Brynden. Queen Talisa pays a visit to Tywin's captured nephews, Martyn and Willem Lannister, and tends to their wounds.
In the Riverlands[edit]
Arya Stark confronts Sandor "the Hound" Clegane about killing Arya's friend Mycah while traveling from Winterfell, but before the Hound can reply, he is taken away in a cart. Arya and Gendry then say goodbye to Hot Pie, who tells them that the Brotherhood has left him at the inn as payment to the innkeeper after proving his skill as a cook.
Locke and his men transport Ser Jaime Lannister and Brienne of Tarth to Harrenhal. Along the way, Brienne and Jaime bicker about their capture, Brienne chides Jaime for his poor swordplay, and Jaime anticipates the men will try to rape Brienne, suggesting she submit to their advances or face being killed. However, he concedes that if he were in Brienne's position he would make the men kill him. At camp for the night, when Locke's men attempt to rape Brienne, Jaime convinces Locke that Brienne's father is rich and would pay ransom to have her back chaste and unharmed. Locke believes Jaime's story and stops the men from raping Brienne. However, Jaime then tries to secure his own release, promising Locke that his father Tywin will reward him with gold and titles if he is returned to him. Locke feigns acceptance but is actually offended by Jaime's offer, sneers that Jaime is powerless without his father, and drives home the point by severing Jaime's right hand, his sword hand.
Production[edit]
"Walk of Punishment" was written and directed by producers D.B. Weiss and David Benioff.
Writing[edit]
"Walk of Punishment" was written by the show creators and executive producers David Benioff and D. B. Weiss, based on material from George R. R. Martin's novel A Storm of Swords. The episode adapts parts of chapters to 15, 16, 18, 20, 22, 24, 28, 32, 34 and 36 of the book (Catelyn II, Jon II, Arya III, Tyrion III, Jaime III, Daenerys II, Daenerys III, Jaime IV, Samwell II and Catelyn IV). The writers have also included original storylines including Theon's flight, Tyrion bringing Podrick to a brothel, and Melisandre departing Dragonstone.[1]
In the scene at the brothel, Tyrion claims that the last prostitute he introduces is one of the few women in the world able to perform "the Meereenese Knot". This is an inside joke referring to the name that Martin gave (after the legendary Gordian Knot) to a complicated structural problem that he had to face while writing the fifth book of the series, A Dance with Dragons. This book had to synchronize the arrival of several characters in the city of Meereen while keeping the chronology and causations in line and informing the reader of events happening in places where no point-of-view character was present. Martin worked on solving "the Meereenese Knot" from 2005 to 2011, and it was one of the main causes behind the late delivery of the book.[2][3]
Directing[edit]
The episode was directed by the writing team itself, although to comply with the rules of the Directors Guild of America only Benioff is credited for directing. For both Benioff and Weiss, it was their first direction experience though the former had previously directed an experimental short film "When the Nines Roll Over".[4]
Casting[edit]
"Walk of Punishment" introduces the Tully family at Riverrun, marking the first appearances of Lady Catelyn's uncle Brynden Tully, played by Clive Russell, and her brother Edmure, played by Tobias Menzies. Edmure Tully is depicted in the show more harshly than in the books.[1] Talking about his character, Menzies described him as "as comic as Game of Thrones gets ... He's a little flawed, really." Dean-Charles Chapman first appears in the role of Martyn Lannister in this episode. In Season 4, however, Chapman returns portraying a different character: Tommen Baratheon, who was played by Callum Wharry in previous Seasons. [5]
Filming locations[edit]
The river Quoile was used to depict the surroundings of the Riverrun castle.
The interiors of the episode were filmed at the Paint Hall Studios in Belfast, the show's base of operations. For the exterior shots the production used many other locations across Northern Ireland: the Redhall State (County Antrim) for the Inn at the Crossroads, the Clandeboye Estate (County Down) for Craster's Keep, Downhill Strand (County Londonderry) as the coast of Dragonstone, and the River Quoile (County Down) as the setting of Lord Hoster Tully's funeral.[6]
The storylines led by Jon Snow and Daenerys Targaryen continued to be filmed in Iceland and in the Moroccan city of Essaouira respectively.
Music[edit]
Main article: Music of Game of Thrones
The band of Locke's men sing "The Bear and the Maiden Fair", heard for the first time in the series with music composed by Ramin Djawadi. The song, a very popular song in Westeros both among the commoners and the nobility, appears often in the original novels. Singing at the head of the group is Snow Patrol's frontman Gary Lightbody, in a cameo appearance.[7]
The closing credits reprise the song in a new version recorded specifically for the series by the indie band The Hold Steady. The group, one of Benioff and Weiss's favourite bands, was chosen because they wanted the rendition "to be bawdy and a little sloppy – drunken musicians getting up on the table and jamming while the rowdy party continues around them".
The decision to place the song at the end of the episode, right after the amputation of Jaime's hand, was made to reinforce the surprise of the viewers: “It’s such a shocking ending and when we read the scene in the books it was so shocking to us. To really hammer home the shock of that moment you need something unexpected. There’s no version of a traditional score that would keep you as off balance as we wanted that scene to leaving you feeling.”[8][9][10]
Reception[edit]
Ratings[edit]
"Walk of Punishment"'s first airing was seen by 4.7 million viewers, setting a new viewership record for the show. Taking into account the viewers of the later repeat the figures rose to 5.8 million.[11] In the United Kingdom, the episode was seen by 1.173 million viewers on Sky Atlantic, being the channel's highest-rated broadcast that week.[12] In the United Kingdom, the episode was seen by 1.093 million viewers on Sky Atlantic, being the channel's highest-rated broadcast that week.[13]
Critical reception[edit]
The episode was praised by critics; review aggregator Rotten Tomatoes surveyed 21 reviews of the episode and judged 95% of them to be positive with an average score of 8.3 out of 10. The website's critical consensus reads, "A bit of well-placed levity perfectly compliments the shocking final scenes of 'Walk of Punishment', adding up to hands down the most thrilling episode of the season so far—minus one hand."[14] Matt Fowler, writing for IGN, rated the episode 8.8/10, writing "A shocking chop and a rollicking rock song led us out of a strong Thrones episode."[15] Writing for the A.V. Club, David Sims rated the episode an A-.[16] Also at The A.V. Club Todd VanDerWerff gave the episode another A-, praising its quickening of narrative pace.[17] Time magazine reviewer James Poniewozik praised the episode, writing "...as a fan of fantasy fiction since I was a kid–is that it has a level of ugly realism missing from much of the genre."[18]
References[edit]
^ Jump up to: a b Garcia, Elio. "EP303: Walk of punishment". westeros.org. Retrieved April 15, 2013.
Jump up ^ Martin, George R.R. "Guarded Optimism". Not a blog. Retrieved April 15, 2013.
Jump up ^ Martin, George R.R. "Talking About the Dance". Not a blog. Retrieved April 15, 2013.
Jump up ^ Lash, Jolie. "Game Of Thrones: Producers David Benioff & D.B. Weiss To Direct During Season 3". Access Hollywood. Retrieved April 15, 2013.
Jump up ^ Lash, Jolie. "Game Of Thrones: Access Countdown To Season 3 Q&A — Tobias Menzies Talks Edmure Tully". Access Hollywood. Retrieved April 15, 2013.
Jump up ^ "Day 23: Filming continues in NI, peep these new pics from the set". WinterIsComing.net. Retrieved April 15, 2012.
Jump up ^ Power, Rob (April 16, 2013). "Game Of Thrones 3.03 "Walk Of Punishment" REVIEW". SFX. Retrieved April 16, 2013.
Jump up ^ Hibberd, James (March 5, 2013). "'Game of Thrones' and the Hold Steady team for sesson 3 song -- EXCLUSIVE". EW.com. Retrieved April 15, 2013.
Jump up ^ Hibberd, James (April 14, 2013). "'Game of Thrones': Nikolaj Coster-Waldau on Jaime's big surprise". EW.com. Retrieved April 16, 2013.
Jump up ^ "The Hold Steady Record Song for 'Game of Thrones'". Rolling Stone. March 5, 2013. Retrieved April 16, 2013.
Jump up ^ Hibberd, James (April 16, 2013). "'Game of Thrones' sets ratings record for latest episode". Entertainment Weekly. Retrieved April 16, 2013.
Jump up ^ "Top 10 Ratings (1 - 7 April 2013)". BARB. Retrieved January 19, 2017.
Jump up ^ "Top 10 Ratings (15 - 21 April 2013)". BARB. Retrieved January 19, 2017.
Jump up ^ "Walk of Punishment". Rotten Tomatoes. Retrieved May 3, 2016.
Jump up ^ Fowler, Matt (April 14, 2013). "Game of Thrones "Walk of Punishment" Review". IGN. Retrieved April 15, 2013.
Jump up ^ Sims, David (April 14, 2013). ""Walk of Punishment" (for newbies)". The A.V. Club. Retrieved April 15, 2013.
Jump up ^ VanDerWerff, Todd (April 14, 2013). ""Walk of Punishment" (for experts)". The A.V. Club. Retrieved April 15, 2013.
Jump up ^ Poniewozik, James (April 15, 2013). "Game of Thrones Watch: That's What the Money's For!". Time. Retrieved April 15, 2013.
External links[edit]
Wikiquote has quotations related to: Walk of Punishment
"Walk of Punishment" at HBO.com
"Walk of Punishment" on IMDb
"Walk of Punishment" at TV.com
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Game of Thrones episodes
Seasons: 1
2
3
4
5
6
7
Season 3
"Valar Dohaeris"
"Dark Wings, Dark Words"
"Walk of Punishment"
"And Now His Watch Is Ended"
"Kissed by Fire"
"The Climb"
"The Bear and the Maiden Fair"
"Second Sons"
"The Rains of Castamere"
"Mhysa"
Retrieved from "https://en.wikipedia.org/w/index.php?title=Walk_of_Punishment&oldid=804219123"
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