Gastrointestinal Overview

muscularis mucosae sumucosa serosa directionality

-This is a cross section here: around the lumen, there is the mucosa and the ________ _______ and then then ___________--> 2 layers of muscle: circular and longitudinal muscle layer,--> ________ These 2 muscle layers: it wouldn't make sense for them to be activated at the same time. Because they have the opposite _________ effects in essence, so when circular layer contracts at the same time the longitudinal layer in that section will be relaxed and vice versa.

gastric epithelial parietal

Anatomy of the stomach: The epithelial cells form these grooves--> the ________ glands. -on top: most of them superficial _________ cells -getting deeper into grooves more specialized cells: most important one are _________ cells--> secrete HCl, hydrochloric acid.

right away duodenum Calcium, Iron and Folate small intestine

Nutrient Digestion and Absorption: -nutrient uptake is sort of not equally absorbed through small intestine. Most of nutrients are absorbed _____ ______, and there is less and less absorption the further the food progresses. so these arrows here, essentially show the bigger the arrow- the higher the absorption for the indicated molecule in the area. The highest absorption of carbohydrates, proteins and lipids is initially in the ____________, so very early in the intestine. It's similar for ______, _______ , and _______. The bile acids : They are secreted in an earlier part of _______ ________, but later on they are absorbed again for recycling purposes. This is another indication that all of these areas are highly specialized.

salt and water mucus amylase lingual lipase size viscous glyoproteins mucus gravity peristalsis dissolve HCl pepsin mucus stored

Organs of the GI tract/ Functions: Mouth and pharynx: Endocrine Secretions, Functions: -______ and _______ -moisten food -_______ - lubrication -________ - polysaccharide- digesting -_______ _______ -fat-digesting enzyme overall function is to reduce______ of pieces and particles- done by chewing, food is also mixed with saliva and mucous- basically a more _________ fluid with buffers salt and a high content of ____________- where it gets its viscocity. The chewing and mixing also serves to lubricate the fluid, because if you have a dry piece of bread in your mouth and you try to swallow it with minimal chewing--> very unpleasant. There are also enzymes secreted in the mouth to digest carbohydrates/ polysaccharides like Amylase and Lingual Lipase that starts the fat digestion. -chew on sour dough bread for a long time--> as you keep chewing it takes increasingly sour until it tastes like candy -- proves that the amylases are digesting the polysaccharides already in your mouth. Esophagus: Endocrine secretions, functions -________ lubrication , to move food down to stomach -mostly the food goes down esophagus assisted by _______, also some ________ (muscle assisted movement), there is more mucus secreted in the esophagus so food doesn't stick to it and it's more lubricated. Sometimes if you swallow a sour or nasty pill they'll get stuck in this area. Stomach: endocrine secretions, functions: -store, mix, _________- begin digestion, emptying into intestine. -_______ solubilization of food, kill microbes -________ protein- digestion enzyme -_________ lubricate and protect epithelia surface -major functions are the food is _______, mixed with HCl

Pharynx esophagus

Organs of the GI tract: -series of hollow organs -series of accessory organs and glands that secrete into these hollow organs --> specialized function --> separated by sphincters -food enters through mouth, then ___________--> _________--> stomach--> small intestine (duodenum, jejunum, ileium), large intestine (cecum, colon, rectum)

H+ increases

Parietal cell: -Secrete ______(H/K ATPase) into the lumen -Intracellular pH__________ (OH increase) -CO2 and OH- combine via carbonic anhydrase -->HCO3 exits toward blood via AE2 -Secrete Cl- into lumen -Net HCl secretion into lumen

lipids, carbohydrates, and amino acids

Both the small and large intestines absorb water and electrolytes, but only the small intestine absorbs ________, _________, and _______ _______.

longer 6 2.4 surface area villi

Then for the small and large intestine: -the small intestine: smaller diameter but a ________ length. - about ____m in length -the large intestine- around _____ m long small intestine- has dramatically increased ______ _______. in large intestine you have crypts- indentations with specialized cells in groove. -also have crypts in small intestine, but in addition to this you also have the _______ on top (the rocky mountains on top plus the valleys)

Celiac

There are different diseases involved with small intestine: __________ disease- autoimmune disease against gluten- in mainly grains --> leads to malabsorption of many vitamins and other nutrients and diarrhea.

intake vomiting diarrhea plasma to lumen Autonomic Plexus Hormone Septic

Water balance: -inadequate _______ -excessive loss --> ___________ or ___________ --> rapid shift from ________ to _______ (Dumping Syndrome) Control Systems: -_____________ dysfunction (secondary to Diabetes Mellitus) -_________ dysfunction (Achalasia, Hirschsprung's) -___________ secretion dysfunction Barrier loss: -_________ shock

Lips Isthmus of the fauces Upper esophageal Lower esophageal Pyloric Ileocecal salivary gastric pancreas, liver, gallbladder and intestinal

-each of these sections is separated by the most part through sphincters: ______: external sphincter that opens of closes for food -when you swallow you engage the skeletal muscles because as you know you have full control over when you swallow, and in the later part of the esophagus is smooth muscle so there is no control over it You'll probably remember all these sphincters: -Lips -_________ _____ ___ _________- between the mouth and throat -_______ _______ sphincter - voluntary , between the throat and esophagus - _______ ________ sphincter- involuntary, between the esophagus and stomach --> these are phagal sphincters on the upper and lower ends -__________ sphincter -b/t stomach and small intestine -__________ sphincter - b/t small and large intestine -Anus- b/t large intestine and outside different glands that secrete things into this hollow organ system: -in the mouth : _________ glands -in the stomach: _________ glands -in the small intestine: ________, _________, ___________, and _________ glands

muscularis mucosae absorptive and secretory collagen, elastin, serosa few densely varicosities Meissner's circular longitudinal

A mucosal layer consists of a layer of epithelial cells, a lamina propria, and a _______ ________. The epithelial cells are specialized to carry out _________ and ________ functions. The lamina propria consists primarily of connective tissue, but it also includes blood and lymph vessels. The muscularis mucosae consists of smooth muscle cells; contraction of the muscularis mucosae changes the shape and surface area of the epithelial cell layer. Beneath the mucosal layer is a submucosal layer, which consists of ________, _______, glands, and the blood vessels of the gastrointestinal tract. Motility of the gastrointestinal tract is provided by two layers of smooth muscle, circular muscle and longitudinal muscle, which are interposed between the submucosa and the _______. The longitudinal muscle layer is thin and contains _______ nerve fibers, whereas the circular muscle layer is thick and more _________ innervated. Neurons do not make true synapses on the gastrointestinal smooth muscle fibers; rather they release transmitter from __________ along the length of their axons. Two plexuses, the submucosal plexus and the myenteric plexus, contain the nervous system of the gastrointestinal tract. The submucosal plexus (___________ plexus) lies between the submucosa and the circular muscle. The myenteric plexus lies between the _________ muscle and the _________ muscle.

pancreatic brush border lipase, chymotrypsin, and amylase carbohydrates and proteins secretory 8 to 9

Digestion is completed in the small intestine by the action of both __________ enzymes and enzymes at the ______ _____ of the small intestine. Pancreatic enzymes, which include _______, ________, and _________, are critical for the digestion of lipids, protein, and carbohydrates, respectively. The enzymes on the luminal surface of the small intestine (e.g., brush border disaccharidases and dipeptidases) complete the digestion of __________ and _________. Digestion by these brush border enzymes is referred to as membrane digestion. The material presented to the small intestine includes both dietary intake and ________ products. The food material entering the small intestine differs considerably from that of the ingested material because of the mechanical and chemical changes just discussed. The load to the small intestine is also significantly greater than that of the ingested material. Dietary fluid intake is 1.5 to 2.5 L/day, whereas the fluid load presented to the small intestine is ____ to _____ L/day. The increased volume results from substantial quantities of salivary, gastric, biliary, pancreatic, and small intestinal secretions. These secretions contain large amounts of protein, primarily in the form of the digestive enzymes discussed earlier.

lumenal/ apical interstitial Glucose peptides monomers monosaccharides monoglycerides

Enzymes of the digestive tract: membrane that separates the lumen and the intestinal epithelial cell--> ________/__________ membrane basolateral membrane is facing ________ space between intestinal epithelium of cells and interstitial space. -__________ can be absorbed through luminal/ apical membrane through highly specialized membrane transport proteins. -Proteins are usually first digested into _________ or individual amino acids and there are dedicated transporters for this. Luminal hydrolysis of polymers to ___________. -polysaccharides or disaccharides - they are cleaved into the ______________ and then absorbed and triglycerides - 2 of the fatty acids are cleaved and then the fatty acids and the ____________ are absorbed for the most part.

cephalic active transport vasodilator hyperosmolality cholecystokinin kinins luminal Bile acids fats increases muscularis submucosal mucosal decreases

First, the CNS initiates an "anticipatory" response that increases splanchnic blood flow with the mere thought of food—corresponding to the "__________ phase" of gastric and pancreatic secretion. Second, mucosal metabolic activity during digestion and absorption primarily depends on the rate of ________ _________ of substances across the epithelium. These activities consume O2 and produce ___________ metabolites (e.g., adenosine and CO2) that increase blood flow locally. Third, the absorption of nutrients generates ______________ in both the blood and the lymphatic vessels of the villus. Hyperosmolality itself stimulates an increase in blood flow. Fourth, during digestion, the gastrointestinal tract releases several hormones, some of which are vasoactive. Of these, _____________ and neurotensin (see Table 41-1) may reach high enough concentrations in the local circulation to promote intestinal blood flow. The intestinal epithelium also releases various _______ (e.g., bradykinin and kallidin), which are powerful vasodilators. The magnitude of the postprandial hyperemia further depends on the nature of the _________ content. _____ ______ and partially digested_____ are particularly effective in promoting hyperemia by acting on chemoreceptors in the intestinal mucosa. The circulatory system does not distribute the increased splanchnic blood flow equally to all digestive organs, nor does it distribute the flow equally throughout the wall of even one segment of bowel. During and after a meal, blood flow __________ sequentially along the gastrointestinal tract, first in the stomach and then in more distal segments of the intestine as digestion proceeds. In all segments, blood flow through the ___________ layers primarily provides nutrition for the smooth muscle cells. However, flow through the villi and ___________ vessels supports the absorption of food- stuffs as well as the secretion of electrolytes, fluids, and enzymes. After a meal, splanchnic blood flow is elevated for 2 to 4 hours, primarily reflecting the vasodilation in the ___________ layer. As in the heart and skeletal muscle, muscle contraction in the intestine (i.e., peristalsis) __________ blood flow, probably as a result of the compression applied by the muscularis in conjunction with the distending pressure of the luminal contents.

carbohydrates and lipids stomach lingual lipase lipase

For __________ and __________, these digestive processes are initiated in the mouth by salivary and lingual enzymes: amylase for carbohydrates and lipase for lipids. Protein digestion is initiated in the ________ by gastric proteases (i.e., pepsins), whereas additional lipid digestion in the stomach occurs primarily as a result of the _______ ______ that is swallowed, although some gastric ______ is also secreted. Carbohydrate digestion does not involve any secreted gastric enzymes.

chyme Segmental Peristaltic serotonin decrease vomiting increase antiemetics

For the food to get to this long tube system there has to be a mechanism to push it forward but also to mix it so that all of the enzymes can interact with all of the macromolecules and break them down. -Once your digestive system deals with it it is called _________. There are two different kinds of motility: 1) __________ (at top): the muscle contracts and splits this chyme bolus, in next step, contraction occurs outside of these two bolus paths to push it back together into one chyme bolus. This will lead to mixing 2) __________ Contraction:Leads to propulsion, to move chyme/food forward in the GI tract. One group of ligand-gated ion channels involved in peristalsis are the _________ receptors (these are her favorite ligand- gated ion channels****) . During pharm, you'll learn there are antidepresants that act as serotonin reuptake inhibitors, side effect is that they increase peristalsis and _________ transit time. That's something interesting to keep in mind for patients that take these drugs. On the other hand. Chemotherapy induced ________ is treated very well with serotonin receptor (5-HT) antagonists - act as anti-emetics, these are like the most, they are very important for cancer and chemotherapy support but also other situations of emesis) 5-HT3 receptors (activity increases peristalsis_ --> 5-HT-RUI ________ peristalsis and decrease transit time -->5-HT- antagonists act as ____________

Achalasia sphincter pH acid electrolyte and water cholesterol enzymes storage Malabsorption Enzyme Bile salt nutrient

Potential pathologies: Motility: -Hyper or hypo (diarrhea or constipation) -Mechanical or functional blockage: Can result from loss of coordinated muscle function ________, Hirschsprung's -->can result from _________ problems (pyloric stenosis) --> can lead to vomiting & _____ imbalance. Secretion: -Excess ______ leading to ulcers (Zollinger-Ellison, H. Pyloris) -Excess ________ and _______ secretion (Cholera) & dehydration -Excess ___________ production -Deficient _________ or bile salts (malabsorption ) -Hepatic _______ diseases. Digestion and Absorption: -___________ syndromes (osmotic diarrhea, nutrient deficiency) -__________ deficiency (pancreatic disease, mucosal dysfunction) -_______ ______ deficiency (liver disease) -Deficient or inappropriate ________ intake

carbohydrates, fats, proteins and nucleic acids bicarbonate bicarbonate pH monosaccharides, DNA and proteins bile bile salts bicarbonate metals digestion fluidity mucus storage salt and water chyme

Small Intestine: endocrine secretions, functions: -enzymes and bicarbonate secretion, non-digestive endocrine function -enzymes, digestion of ___________, _____, _________, and _______ _______ -_______________, neutralize HCl -the pancreas secretes different enzymes and __________ (so in the stomach you had the HCl that activates pepsinogen to pepsin and other functions, that's a very acidic environment and your body doesn't want to maintain that for the rest of the digestive process) so early on in the intestines the pancreas will raise the _____ of the secretions and make it closer to neutral again. There's different enzymes secreted from the pancreas that help with the cleavage of all kinds of nutrients polysaccharides, fats - triglycerides and ___________, ______, and _______ are also cleaved. next secretions would come from Liver and Gallbladder: -Endocrine secretions, functions -secretion of _______, non-digestive endocrine functions -______ _____ -solubilize water-insoluble fats, makes them availible for absorption, later reabsorbed and recycled again. -________- secretion of this to raise the pH further -organic waste products and trace _________- elimination of feces- like molecules that have detoxified through oxidation for example and other processes and also trace metals excreted by the liver this way. The end result is that these waste products are eliminated in the feces. -The Small Intestine: En secretions, fxns: -digestion and absorption of most substances; mixing and propulsion of contents -enzymes- food __________ -salt, water-maintain ________ and luminal contents -_______, lubrication. --> will further assist in breaking down and absorbing these molecules. The Large Intestine: -_________, concentration; absorption of _______ and ________; mixing and propulsion -mucus- lubrication --> the _________ is further stored and concentrated so water is also reabsorbed again, and it's mixed and once you are ready the large intestine leads to defecation in the end.

120 .3

Small intestine has a very large surface area: ______m^2 if unfolded Large intestine: ____m^2 - small

hemodynamis increases HYPEREMIA decreases increases compliant 1/2

Splanchnic Blood Volume: Regulation of blood volume within GI organs: -To maintain stable systemic _________ -1L of blood can be recruited from splanchnic vasculature (compliant splanchnic veins) -blood flow to GI tract __________ up to 8-fold after a meal (POSTPRANDIAL ______________) -Sympathetic activity ________ and parasympathetic activity _________ blood flow. The total blood volume that's in the liver, intestine, and spleen together is 1,650mL and 1050mL (1L) can be mobilized so the vasculature is very ___________(the veins), so the diameter can be regulated and by regulating the diameter the amount of platelets in the system can be manipulated by a huge amount. It is way more than _____ of the blood volume in this organ area and can be mobilized -and so after a meal the blood flow to the GI tract increases and this can be up to 8 fold- why it's tricky to eat a giant meal and go for a run, because your muscles will have to fight with your GI tract who will get the blood, not fun sometimes.

blood redundancy Celiac mesenteric ischemia Countercurrent venules

The Splanchnic Circulation: apart from digesting, there's also sort of a ________ reservoir that can be recruited in the GI tract. The different GI organs get their blood supply from different arteries so there is a lot of __________ which is a safety mechanism to ensure this important organ system is always supplied with sufficient blood. redundancies avoid ischemia. _______ artery: blood supply to spleen, stomach, and pancreas. Superior and inferior __________ arteries: blood supply to large and small intestine, part of pancreas and stomach. Extensive interconnections /redundancies (avoid ___________) _______________ in villus can lead to shortcutting of oxygen/ permeable from arterioles to venules without having to traverse the entire length of the villus. -Some books don't have a good image for it- the countercurrent, in the villi if the blood flow is reduced, the blood flow can shortcut from the arterioles to the _________. Which in essence leads to the oxygen not coming all the way to the tip, so that can be a problem if the blood supply to these villi is compromised then there may be saldus?? at the top of the villus

Capillaries flow anoxic solutes (e.g., Na+) increases tip oxygenated reduced falls

The arrangement of microvessels within a villus is like a fountain (Fig. 24-7D). The incoming arteriole courses up the center of the villus, branching into many capillaries along the way to the tip of the villus. Capillaries converge into venules and carry blood back to the base of the villus. ________ also interconnect the arteriole and the venule all along the villus. These microvessels are permeable to solutes of low molecular weight or high lipid solubility.The arrangement just described can create a countercurrent exchange system that enables permeable solutes to move from the arteriole to the venule without having to traverse the entire length of the villus, particularly under conditions of low _______. With prolonged transit times, blood-borne O2 can diffuse from the arteriole to the venule before reaching the tip of the villus, which makes it susceptible to _________ damage. The situation is just the opposite for _____________ that the villus epithelium absorbs during digestion. These solutes enter capillaries and then pass into venules. As the venous blood travels toward the base of the villus, the solute can diffuse out of the venules, into the interstitium, and then into the arterioles. In this way, the solute concentration in the arterial blood __________ as the blood flows to the tip of the villus. This "trapping" process increases the interstitial osmolarity near the_______ of the villus, in a manner analogous to the mechanism that maintains high osmolality at the tip of the renal medulla . In contrast, when the intestinal mucosa is adequately perfused (e.g., at rest and particularly after a meal), the tips of the villi are well ____________ (as in Fig. 24-7D), the effects of countercurrent exchange are ________, and the osmolality within the villi _______.

Motility salivary pancreas liver absorbable electrolytes

The functions of the gastrointestinal tract are digestion and absorption of nutrients. To serve these functions, there are four major activities of the gastrointestinal tract. (1) __________ propels ingested food from the mouth toward the rectum and mixes and reduces the size of the food. The rate at which food is propelled through the gastrointestinal tract is regulated to optimize the time for digestion and absorption. (2) Secretions from the ________ glands, _________, and _______ add fluid, electrolytes, enzymes, and mucus to the lumen of the gastrointestinal tract. These secretions further aid in digestion and absorption. (3) Ingested foods are digested into __________ molecules. (4) Nutrients, __________, and water are absorbed from the intestinal lumen into the bloodstream.

bicarbonate drops stomach specific fatty

The pH changes while the food / chyme moves along GI tract. The stomach is very acidic and pH increases while food moves along small intestine due to secretion of _________. In the beginning of large intestine- pH ________ a little bit again and then further increases. Why is it beneficial to have such a low pH in the stomach--> it kills things. If you eat food that's contaminated with bacteria that could cause GI problems, food gets mixed with very low pH in the stomach and then that kills most bugs unless you have ingested a lot of this trouble causing bacteria and that will move on and infect/ cause problems. It controls what gets through your system and stays in your GI tract alive. However, there is a whole research area that has developed in the last few years. Study of the Microbiome! - inside our GI tract if you count the bacterial cells in your GI tract, there is more bacteria in your GI tract at any given time (unless you are on high dose antibiotics at any given time and then you have cells in your entire body). -Numbers of colony forming units: lowest in _________, increases as it goes through the digestive tract. Bacteria that are found in normal healthy human are __________ for the different areas of the GI tract, what we eat can change the colonization of the bacteria. -if you eat a ton of _______ meat all of the time, you get more of these Bacteroides- not very good for other disease (very complex) there are now studies that transplant bacteria between different ppl/ manipulate colonization to treat many different diseases.

2 ground antrum Retropulsion much slowly salty

The stomach has some quality control to determine if the food is small enough to go into the intestine: -one number is that food has to be <_____mm!!! to go to small intestine. Really really small number, she doesn't believe it (she has kids who eat corn and it comes out) -also peristaltic waves that move the chyme through the pylorus. Bolus is pushed toward the closed pylorus. Also the food once it's trapped here it's _________ a little more, and you can hear the grinding if you go without breakfast (grinding on empty). The _________ churns the trapped material. stomach can also push the food backwards with ___________- the bolus is pushed back into the proximal stomach. How long it takes food to leave the stomach depends on: -what was in the food and also how _______ was it. -blue curve: very fatty meal--> very ________ digested, until all of it is out it will take forever -red curve: very ______ meal will increase the rate of gastric emptying (what happens with the gels people take during sports, if it's salty and sugary--> throw it into empty stomach it leaves right away and you can pretty much feel the sugar kicking in very rapidly.

mucus high low Viscous Fingering parietal

The stomach is very acidic inside- how do we not digest ourselves? -how the protection layer works: --> there's a thick, very viscous layer of _______ on the epithelial cells in the stomach, and this mucus has a lot of bicarbonate secreted into it, so it has a relatively _____ pH, viscous area in the bottom of the gastric glands. The pink area at the top in the gastric lumen is where the _____ pH is. The hydrochloric acid gets through this viscous layer through ________ ________ (high pressure, very acidic; tunnels that form through this mucus surface, but no later spread). because the _________ cells that secrete the HCl, they essentially make a little tunnel that goes through this mucus and shuttles the HCl into the pink area.

mucosal serosal

The wall of the gastrointestinal tract has two surfaces, mucosal and serosal. The _________ surface faces the lumen, and the _______ surface faces the blood

crypts submucosa serosa

The wall of the gastrointestinal tract. A, The wall of a generic segment of the gastrointestinal tract consists of the following structures, from inside to outside: an epithelial layer with ________, lamina propria, muscularis mucosae, ____________, the circular and then the longitudinal layer of the muscularis externa, and _________. B, The colon has the same basic structure as the small intestine. Some of the epithelial cells are on the surface, and others are in the crypts that penetrate into the wall of the colon.

arder inflammatory

Transit Times: Bristol Stool Chart -the longer the food stays in the GI tract the h________ it will be, so if you have diarrhea it's like a puddle- very liquidy may indicate poisoning or _________ process. The more water that is extracted from this process the harder it gets. If the chyme stays in the GI tract for too long, it can get extremely hard and painful to excrete. This is the state it would be in for a constipated patient at top.

buffered mast histamine blood flow mucus decrease Pepsin 3.5 inactive H+ histamine more injury esophagus, duodenum. 3.5 3.5 7.5

When the mucus layer is damaged this can be very devastating because then the protons are not ________ by this more basic mucous. the protons will activate ______ cells--> which release _________--> which signals further. If it's just a little protons leaking through (some mucus problems here and there) then this will lead to an increased ______ ______and the problem will solve itself, because increased blood flow leads to more ________ production. However, if the mucus layer is severely destroyed this will lead to a _________ in blood flow and then because the ________ that is also secreted will start chewing up the proteins and cells. -usually pepsin is only active at a pH of ______ or lower, and when you have some mucus within the gastric glands the pepsin is _________ at this high pH so that's why then the pepsin can't chew up the proteins of the cells. Damaged mucus layer: -_____ penetrates epithelial cells and activates mast cells, release of ________, inflammation --> Mild: increase in blood flow, _______ mucus. --> severe: decrease in blood flow, cell ________ Peptic Ulcer: -breaking in lining of _________, _________. -pepsin (proteases produced in the stomach) --> maximal activity below pH_____ --> Reversible inactivation >_____ --> Irreversible inactivation > _____

autoimmunity diabetes bacteritis autoimmune

from a Microbiome study in 2015: looked at children who were at a high risk to develop type 1 diabetes (insulin resistant diabetes) split the kids into two groups: -One ate high fat, high gluten, low resistance starch diet, and the other half a low fat, low gluten, high resistant starch diet - the kids that were on upper diet had significantly higher risk to develop ___________ and progress into __________, the ones in the other food group were sort of protected. The study looked at kids when they started being introduced to solid foods. Essentially if you know the family history and have an infant you can influence the future of diabetes for that infant significantly by talking to the family about diet. -High fat diet leads to increase in __________, there is less mucin, tight junctions that keep the epithelial cells connected are not that tight anymore and larger molecules can now get into the system between the epithelial cells and that can trigger ___________ reactions. There are a whole host of autoimmune diseases that can be linked to diet in this way: --> Multiple sclerosis, diabetes, as you can see here it's very many diseases. The opposite can happen with the other diet.

1.5 2 1.5 .5 1 small 6.5 diarrhea glucose sodium chloride .1

the hardening of the stool- process of removing more and more water out of chyme , impressive what our gi tract does with water. Average person gets 2.0L/ day of water by drinking (not enough - especially here) -_______L/day saliva added to the food by saliva to make it glide through whole thing. Water for each step: -Stomach: ___L/day gastric secretion -Pacreatic secretion: ______L/day -Bile secretion: ____ L/day -Small Intestine Secretion:___L/day --> that adds up to 8.5L/ day (more than two gallons of water) -so water is reabsorbed by the ______ intestine at the same time. It reabsorbs _____ L/day --> a lot of water. So if something that irritates your small intestine gets ingested and this reabsorption stops you end up with a lot of water in your GI tract and you get bad __________-> can lead to extreme water losses. The easiest way to help the patient is to provide some where the ______ ______ _______ solution and that will rehydrate them. 6.5 L are reabsorbed in small intestine: 8.5 L secreted so 8.5-6.5L = 2L passed onto the colon and this area most of that water is reabsorbed, so in the end you only lose about 1/2 glass of water in feces around_____ L/day. And you know there are other ways for the body to eliminate the water.

Small Intestine serotonin retral stomach sphincters duodenum

want to go back a little bit: food moves in one direction from mouth through anus and the process that pushes it forward is through peristalsis, but when somebody vomits.. most of the food contents that comes out- where do you think this process gets messed up and reverses direction--> stomach in part correct, it's not the stomach contracting as a muscle, it is the ________ ________!- let's say you have food poisoning and some chemical triggering of __________ receptors and also other receptors of small intestine and it leads to a ________ peristalsis in the small intestine. So instead of moving the food coordinated foward and away from the mouth the small intestine goes into a process called retral peristalsis, so it pushes the food into the ___________. For this to be successful, you have to open several sphincters because the food is thrown out from small intestine, and it will take stomach contents with it because it is moving through there, but the stomach is sort of passive, so these ___________ will all open in a concerted fashion to allow this to happen. Vomiting is very efficient- one time and done sometimes, body gets rid of whatever is causing it (bacteria, viruses, etc) so for many things very efficient way to rid the problem. - occurs from the ____________- where the contents are technically from .