Digestive System Flashcards
What is the primary function of digestive system?
Primary Function of Digestive System
* To break down food and/or liquids into smaller units of absorbable nutrients which are used by your body to generate energy
On average how
long do you think it takes for the sandwich you ate at lunch to
completely pass through your digestive tract?
24 hours
What is the Alimentary canal?
Alimentary canal
* Structures form long tube that breaks down food
* It takes approximately 24 hours from ingestion to defecation
What are the Accessory digestive organs?
Accessory digestive organs
* Participate in digestive process but food does not pass through
these structures
* Examples:
- Liver
- Pancreas
- Gallbladder
- Salivary glands
What is Ingestion?
Ingestion
* Put food into mouth
What is Propulsion?
Propulsion
* Movement of food through canal
* Swallowing is voluntary
* Peristalsis is involuntary
What is Mechanical digestion
Mechanical digestion
* Physical breakdown of food particles
* Chewing, churning, segmentation
What is Peristalsis?
Peristalsis
* An organized contraction and relaxation of smooth muscle layers that propels food through the alimentary canal in one direction
- Ex. cookie dough gets squeezed out
- Allows you to eat upside down
What is Segmentation?
Segmentation
* Contractions of smooth muscle move chyme (food product being digested) back and forth within canal to allow mixing and further breakdown
- mix up food particles and digestive enzymes
- homogenous mixture of food and enzymes
What is Chemical digestion?
Chemical digestion
* Enzymes and chemicals break down food
What is Absorption?
Absorption
* Particles (ex. Sugars, fatty acids, etc.) are
transported from canal into blood and lymph
capillaries
What is Defecation?
Defecation
* Indigestible products are eliminated as feces
What are the layers of the Alimentary Canal
- The inner canal = lumen
- There is a consistent layering of tissues that form most of
the alimentary canal (there are some exceptions to be noted later) - From lumen to outer layer:
- Mucosa: lines lumen
- Submucosa: support layer
- Muscularis externa: muscle layer
- Serosa: outer surface
What are the 3 sublayers of Mucosa?
3 sublayers:
1. Epithelium
* Type varies by location
* Mucus production, absorption, protection, etc.
* Continuous & contains many digestive glands
2. Lamina propria (loose areolar)
* Capillary rich (absorption)
* MALT = mucosa associated lymphoid tissue
* Provides defense
3. Muscularis mucosa (thin layer smooth
muscle)
* Localized movements, helps glands expel
contents
What are the components of submucosa?
Submucosa
* Similar to loose areolar CT but more collagen fibers (provide support)
* Highly vascularized
- Nutrient absorption
* Glands connecting to lumen may project to submucosa
* Submucosal nerve plexus
- Control of muscle cells, glandular secretions, etc. (more on this later…)
What are the components of Muscularis Externa?
Muscularis Externa
* 2 layers smooth muscle (stomach has 3)
* Circular: inner layer, typically squeezes tube
* Longitudinal: outer layer, typically shortens tube
* Peristalsis and segmentation
* Myenteric nerve plexus
* Innervates muscularis externa and is between longitudinal and circular muscles (more on this later…)
What is the enteric nervous system?
- The enteric nervous system controls smooth muscle and
glands of alimentary canal - Considered the “brain in the gut” - - Has as many neurons as the entire spinal cord
- Reflex arc exists (sensory neurons –> interneurons –> motor neurons)
- Made of two nerve plexuses within the wall of alimentary canal
- Submucosal nerve plexus
- Myenteric nerve plexus
- Is influenced by the autonomic nervous system
What are the components of Serosa?
Serosa
* Found around organs within abdominal cavity
* Simple squamous epithelium + a thin loose areolar CT = Serous membrane
What is esophagus lined with?
- The esophagus is lined with adventitia (a fibrous CT)
- The esophagus is not contained
within a body cavity lined with a
serous membrane
What is Enteric Nervous System?
Enteric Nervous System
* Is located entirely within the wall of the alimentary canal
* Nerve plexuses allow for a localized response within visceral organs
* Partly independent of central nervous system
* Myenteric nerve plexus
* Submucosal nerve plexus
What is the Myenteric nerve plexus?
Myenteric nerve plexus
* Controls peristalsis and segmentation
* Within muscularis externa
What is the Submucosal nerve plexus?
Submucosal nerve plexus
* Controls secretions of glands & muscularis mucosa contractions
* Within submucosa
What is the Submucosal nerve plexus?
Submucosal nerve plexus
* Controls secretions of glands & muscularis mucosa contractions
* Within submucosa
What is the oral cavity?
Oral Cavity
* Mouth
* Ingestion of food
* Mechanical digestion
- Chewing = mastication
* Chemical digestion
- Mixed with saliva that contains amylase
– Starts chemical breakdown of carbohydrates
What is the Anatomy of the Mouth?
Mouth Anatomy
* Stratified squamous epithelium
* Thin submucosa layer anchored directly to underlying bone
* No muscularis externa or serosa/adventitia
* Lips
What is the Anatomy of the Lips?
Lips: margin between skin and oral cavity (lip proper = transition part)
* Poorly keratinized, translucent
- Red color from underlying capillaries
* No eccrine or sebaceous glands
* Lower lip 12X more likely to get nonmelanoma skin cancer
What is the Anatomy of the tongue?
Tongue
* Accessory digestive organ
* Superior surface (the part you see when you say “ah”) iscovered in keratinized stratified squamous epithelium
- Keratin makes it look whitish
* Moves food, helps mix to form bolus
(also involved with speech)
* Filiform papillae
- Rough surface
* Fungiform and circumvallate papillae
- Contain taste buds
What is the Lingual Frenulum?
Lingual Frenulum
* Lingual frenulum
* Fold of mucosa layer
* Connects tongue to floor of mouth
What is being “Tongue Tied”
Tongue Tie”
* If lingual frenulum extends too far forward, the tip of the tongue cannot move and speech is difficult
* Called ankyloglossia
* Makes saying sounds where the tongue touches teeth (letters such as t, z, p)
* Can be corrected surgically
What are the components salivary glands?
Salivary Glands
* Accessory digestive organs
* Exocrine glands
* Produce saliva
What are the components of salvia?
Saliva
* Moistens mouth
* Dissolves food (so can taste)
* Contains digestive enzymes
- Amylase starts breakdown of carbohydrates
- Lipase begins digestion of fats
* Contains mucus (helps swallowing)
* Neutralizes acids produced by bacteria that promote decay (has bicarbonate buffer)
* Antibacterial and antiviral components
What are the cell types of the Salivary Glands?
Cell types
* Serous cells secrete digestive enzymes
* Mucous cells secret mucus
What are the primary salivary glands?
- Parotid gland and duct
- Submandibular gland and duct
- Sublingual gland and ducts
What are the components of Parotid glands and ducts?
Parotid gland and duct
* Largest salivary gland
* Contains serous cells
- Produce watery enzyme-rich secretion
* Empties near 2nd upper molar
What is Mumps?
Mumps
* Viral infection
- Parotid glands swell; painful
What are the components of Submandibular gland and ducts?
Submandibular gland and duct
* Approximately equal amounts of serous and mucous cells
* Ducts open lateral to lingual frenulum
What are the components of Sublingual gland and ducts?
Sublingual gland and ducts
* Mostly mucous cells (secrete
mucus)
* Several ducts empty below
tongue
What are the components of teeth?
Teeth
* Accessory digestive organs
* Involved in mastication (= chewing)
* Heterodont dentition
* Different shapes of teeth for different jobs
What are Deciduous teeth?
Deciduous teeth
* “Baby teeth”
* 20 total erupt typically between ages 6 months
to 6 years
What are Permanent teeth?
Permanent teeth
* 32 total that gradually replace deciduous
* “Wisdom teeth” = 3rd molars
* Emerge between 17 and 25 years old (not always
can become impacted and do not emerge, or are
sometimes missing)
What are the regions of a tooth?
Regions of a Tooth
* Crown
- Part above gum line
* Neck
- Narrow, contained within gum tissue
* Root
- Contained within bone
What is the anatomy of teeth?
- Pulp
- Dentin
- Enamel
- Cement
- Periodontal ligament
What is the pulp of a tooth?
Pulp
* Loose areolar CT with blood vessels and
nerves
* Provides nutrients and sensation to tooth
* Odontoblasts create dentin
What is the Dentin of a tooth?
Dentin
* Collagen (from odontoblasts) and
minerals
* Forms bulk of tooth; deep to enamel
* Has radial striations = dentinal tubules
* Can contribute to tooth sensitivity
* No cells or blood vessels
* Harder than bone
What is the Enamel of a tooth?
Enamel
* Hardest substance in body
* 99% calcium salts
(hydroxyapatite crystals)
* No cells or blood vessels
What is the cement of a tooth?
Cement
* Calcified CT that covers root
What is the Periodontal ligament of a tooth?
Periodontal ligament
* Dense CT that attaches cement
of tooth to bony socket
What is a cavity?
Demineralization of enamel and dentin
* Begins with dental plaque
* Biofilm of sugar, bacteria and other
debris on teeth
* Bacteria break down sugars and produce
acids
* Dissolve calcium salts of teeth
(demineralization of enamel)
* Bacteria also produce protein-digesting
enzymes that destroy organic component
of teeth
What is the Root Canal Procedure?
- A root canal may be required when the pulp within the canal
becomes infected - Pulp is drilled out
- Tooth is now “dead”
- Cavity is sterilized and filled
- Tooth is capped off to help strengthen it
What is the Pharynx?
- Pharynx connects oral cavity to
esophagus and nasal cavity - 2 parts
- Oropharynx
- Laryngopharynx
- Muscularis externa has skeletal
muscle for swallowing - *Nasopharynx
What is the Oropharynx?
Oropharynx
* Immediately behind oral cavity
* Made of stratified squamous epithelium
What is Laryngopharynx?
Laryngopharynx
* Inferior to oropharynx
* Made of stratified squamous epithelium
What is the Esophagus?
Esophagus
* Connects pharynx to stomach
* Stratified squamous epithelium
(nonkeratinized)
* Mucous glands in submucosa
and mucosa secrete mucus
- Lubricates bolus of food as passes
through
What is the Muscularis externa of the Esophagus?
Muscularis externa
* Upper 1/3: skeletal muscle
* Middle 1/3: mix of skeletal and smooth
* Lower 1/3: smooth muscle
What is Hiatal hernia?
Hiatal hernia
* Superior part of stomach pushes through esophageal hiatus following weakening of diaphragmatic muscle fibers
- Acidic stomach juices are regurgitated, eroding wall of esophagus (= GERD, gastroesophageal reflux disease)
What is Barrett’s esophagus?
Barrett’s esophagus
* Due to persistent exposure of acidic stomach contents
* Causes lower esophageal ulcers and precancerous epithelium
What is the purpose of the stomach?
- Food spends ~4 hours in stomach
being churned into chyme - Mechanical digestion (churning)
- Chemical digestion (digestive
enzymes and HCl) - Some absorption takes place here
(most absorption occurs in the small
intestine) - Limited to water, alcohol, and drugs
(aspirin)
What is the lining of the stomach?
- The lining mucosa is simple
columnar epithelium - Made entirely of cells that produce
bicarbonate-buffered mucus
(protection) - Lining is dotted with many gastric pits
which open into gastric glands (more
later)
What is the anatomy of the stomach?
- Rugae (= “wrinkles”)
Regions - Cardia
- Fundus
- Body
- Pyloric antrum
- Pylorus (= “gatekeeper”) with pyloric sphincter
- Greater and lesser curvatures
- Sphincters
What is Rugae?
Rugae (= “wrinkles”)
* Folds of mucosa that increase surface area and allow stomach to expand
* Easily holds 1.5 liters of food, can hold 4 liters!
What are sphincters?
Sphincters
* Thickened regions of muscularis externa
* Cardiac sphincter (near heart)
- Prevents food from moving back into esophagus
* Pyloric sphincter
- Controls release of chyme intoduodenum
What are the muscularis layer of the stomach?
Muscularis externa has extra layer:
1. Longitudinal
2. Circular
3. Oblique →innermost
What is the microscopic anatomy of stomach epithelium?
- Mucosa is lined with simple columnar epithelium
- Mucous neck cells
- Gastric pits
- Gastric gland
What is Mucosa of stomach epithelium?
Mucosa is lined with simple columnar epithelium
* All secrete bicarbonate-buffered mucus
* Mucus protects stomach wall from acid and digestive enzymes
What is the Mucous neck cells?
Mucous neck cells
* Secrete mucus (different from mucus produced by epithelium [above], function unknown)
What are Gastric pits?
Gastric pits
* Regions where epithelium cups downward, meets with gastric gland
What are Gastric glands?
Gastric gland
* Connect to lumen through gastric pit
* Contain specialized cells
- Parietal cells
- Chief cells
- Enteroendocrine cells
- Undifferentiated stem cells
What are Parietal cells?
Parietal cells
* Produce and secrete 2 products
- HCl which destroys bacteria
- Gastric intrinsic factor (GIF) which is necessary for vitamin B12 absorption in small intestine
* Vitamin B12 is needed for production of RBCs
What are Chief Cells?
Chief cells
* Produce and secrete pepsinogen (in-active form)
* Also secrete gastric lipase (enzyme)
- Fat digestion
What is Pepsin?
Pepsin breaks down proteins in food
* It is created when pepsinogen mixes with HCl
* active version of pepsinogen
- gastrin stimulates release of HCl and pepsinogen
- Pepsinogen + HCl = pepsin
What are Enteroendocrine cells?
Enteroendocrine cells (= “gut endocrine”)
* Release hormones
- Ex. Gastrin stimulates parietal cells to release HCl)
What are Undifferentiated stem cells?
Undifferentiated stem cells
* Found at junction between gastric pits and gastric glands
* Because of harsh environment, stomach cells are replaced every 3-7 days
What is the purpose of the small intestine?
- Longest segment of canal at ~16 ft
- Longer in cadavers than living people
- Simple columnar epithelium
- Site of most absorption and chemical digestion
- Chyme move through via peristalsis
- Is churned via segmentation
What is the Duodenum
Duodenum (= “12 finger-widths long;” 5%)
* closest to stomach
* Shortest
* Receives a number of substances
- Chyme from stomach
- Digestive enzymes from pancreas
- Bile from liver/gallbladder
What is the Jejunum?
Jejunum (= “empty;” 40%)
* Most absorption occurs here
* second part of small intestine
What is the illeum?
Ileum (= “twisted intestine;” 55%)
* closest to large intestine
* Longest
* Absorption occurs here as well
What are the wall layers of the small intestine?
All typical layers of the alimentary canal
occur in the small intestine
* Mucosa
* Submucosa
* External muscularis
* Serosa
What is the total surface area of the small intestine?
200 m2
- large surface area = more absorption
What gives the Small intestine a large surface area?
Has a very large internal surface area to increase absorption:
1. Length (approx. 16 feet)
2. Circular folds
- contain villi, which contain microvilli
What are Circular folds?
Circular folds
* 1 cm tall
* Increase surface area and forces chyme
to spiral through small intestine
- This slowing allows for increased
absorption of nutrients
What is villi?
Villi
* 1 mm tall
* Made of absorptive cells (= enterocytes)
* Have blood capillaries and a lymphatic
capillary called a lacteal
What is Microvilli on enterocytes?
Microvilli on enterocytes
* 1 um tall
* Called brush border as well
What are the features of the villi?
Associated features
* Lamina propria is highly vascular
* Allows for increased absorption
- Capillaries - Absorb proteins and carbs
- Lacteals
- Absorb fats (which are too large
to enter capillaries)
* Muscularis mucosa
- Moves villi within lumen to increase contact with nutrients
What are the specialized cells of the small intestine?
- Absorptive enterocytes
- Goblet cells
- Enteroendocrine cells
*Intestinal crypts - Undifferentiated epithelial cells
- Paneth cells
- Duodenal glands
What are Absorptive enterocytes?
Absorptive enterocytes
* Found in mucosa
* Majority of epithelial cells
* Lots of mitochondria
- Absorption of nutrients requires energy
* Abundant ER
- Assemble absorbed lipids into chylomicrons
- Lipid-protein complexes
- This structure allows lipids to enter lacteals
What are Goblet cells?
Goblet cells
* Found in mucosa
* Secrete mucus
- Protects surface cells and lubricates chyme
What are Enteroendocrine cells ?
Enteroendocrine cells
* Secrete hormones to control
the release of other substances (ex. CCK and secretin)
What are Intestinal crypts?
Intestinal crypts
* Invaginations of mucosa, between villi
* Epithelial cells produce intestinal juice
- A watery liquid that mixes with chyme
What are Undifferentiated epithelial cells (stem
cells)?
Undifferentiated epithelial cells (stem
cells)
* Intestinal crypts
* Rapid replacement of cells
* New lining every 3-6 days
What are Paneth cells?
Paneth cells
* Intestinal crypts
* At base of crypt
* Secrete enzymes that selectively destroy
unwanted bacteria
* Help maintain healthy microbiota
* Role in protecting stem cells
What are Duodenal Glands?
- Duodenal glands have ducts
that open into intestinal crypts - Found in submucosa of duodenum only
- Secrete alkalinic mucus to neutralize acidic chyme
What are the Lymphoid Tissue in Small Intestine?
- The small intestine has many areas of lymphoid tissue
- MALT = mucosa associated lymphoid tissue
- In mucosal layer of small intestine
- Aggregated lymphoid nodules (Peyer’s patches)
- Located in submucosa of ileum
What is the structure of the Duodenum?
Inputs to duodenum:
* Stomach contributes chyme
* Gallbladder adds bile
- Breaks down fats
- Bile duct and sphincter control release
* Pancreas contributes
- Digestive enzymes
- Pancreatic juice (bicarbonate) that neutralizes chyme
- Main pancreatic duct and sphincter control release
* Hepatopancreatic sphincter is the final control “valve”
What happens when Chyme enters duodenum from stomach
and activates enteroendocrine cells?
- Presence of fats
stimulates release of.- Cholecystokinin (CCK) Signals release of stored bile
- Breaks down fats for better absorption
- Presence of acids stimulates release of…
- Secretin Signals release of pancreatic juice
- Neutralizes acids
What is the anatomy of the Large Intestine?
- Epiploic (= “membrane-covered”) appendages
- Teniae coli (= “ribbons of the colon”)
- Haustra (= “to draw up”)
- Ileocecal valve
- Cecum (= “blind pouch”)
- Colon (4 parts)
What is the Epiploic?
- Epiploic (= “membrane-covered”) appendages
- Fat-filled pouches on outside
What is the Teniae coli?
Teniae coli (= “ribbons of the colon”)
* Longitudinal strips of smooth muscle
* Cause puckering into sacs = haustra
What are the Haustra?
Haustra (= “to draw up”)
* Saclike structures
What is the Ileocecal valve?
Ileocecal valve
* Connects ileum to cecum
What is the cecum?
Cecum (= “blind pouch”)
* Vermiform appendix (off of
cecum)
- Stores beneficial bacteria
What are the four parts of the colon?
Colon (4 parts)
* Ascending
* Transverse
* Descending
* Sigmoid
What type of epithelium would you expect to find lining the large
intestine?
Simple columnar
What is the anatomy of Microanatomy of Large Intestine?
- No circular folds
- No villi
- Absorptive cells = colonocytes
absorb primarily
water/electrolytes - Lots of goblet cells (mucus)
- Reduce friction of fecal movement
- Intestinal crypts with stem cells
- Epithelium is replaced every 7 days
What is the rectum?
- Connects sigmoid colon to anal canal
- Has rectal valves
- Transverse folds that prevent feces being
passed with flatus (gas)
What is the Anal Canal?
Anal Canal
* Epithelium transitions into
stratified squamous
* External anal sphincter
- Skeletal muscle, voluntary
control
* Internal anal sphincter
- Smooth muscle, involuntary
control
What are Hemorrhoids?
Hemorrhoids
* Hemorrhoids = varicose veins
of the hemorrhoidal veins in
anal canal
- External and/or internal
hemorrhoidal vein swelling
* Caused by excessive straining
(baby or defecating)
What are the Accessory Digestive Organs of Abdominal
Cavity?
- Liver
- Gallbladder
- Pancreas
What is the purpose of the liver?
The liver is a chemical processing plant
1. Digestive function: produces bile
2. Metabolic functions: processes blood
coming from stomach and intestines
What is the digestive function of the liver?
- Digestive function: produces bile
* Bile salts break emulsify fats in small
intestine
* Bile is stored in gallbladder until released
into duodenum
What is the Metabolic functions of the liver?
- Metabolic functions: processes blood
coming from stomach and intestines
* Stores some vitamins
* Processes fats and amino acids
* Inactivates drugs and toxins
* Stores glucose as glycogen
* Makes blood proteins
What are the four lobes of the liver?
Has 4 lobes
* Right
* Left
* Quadrate
* Caudate
What is the hepatic portal vein?
Hepatic portal vein
* Gathers blood from
digestive organs and
transports it to the liver
What is the blood supply to the liver?
Blood supply
* Hepatic artery proper
* Hepatic portal vein
* Inferior vena cava
What is the purpose of the Hepatic artery proper?
Hepatic artery proper
* Provides oxygen-rich blood to
liver
What is the purpose of the Hepatic portal vein?
Hepatic portal vein
* Transports nutrient-rich blood
from stomach and intestines to
liver
What is the purpose of the Inferior vena cava?
Inferior vena cava
* Removes blood from liver after
it has been processed
What is Bile?
- Bile, which is produced
in liver, is transported
through ducts to the
gallbladder for storage
How is the anatomy of liver organized?
- Cells of the liver are organized into 50,000-100,000 hexagonally-shaped lobules
How are blood vessels organized in the liver?
- Blood vessels & ducts are organized into
portal triads at corners of lobules
What is in each triad?
Each triad contains
* Bile duct (transports bile out of lobule)
* Portal venule (transports nutrient-rich blood
into lobule)
* Portal arteriole (transports oxygen-rich blood
into the lobule)
What are Hepatocytes?
Hepatocytes are the primary
cell of the liver
* Arranged into plates within
lobules
* Many functions
- Produce bile which is removed
via bile canaliculi
- Metabolize and store
substances from blood
* Great ability to regenerate
What are Liver sinusoids?
Liver sinusoids
* Large capillaries between
plates of hepatocytes
* Site where arterial and
venous blood mix →blood is
carried to central vein
What is the Central veins?
Central veins
* Drains blood from sinusoids out of liver
What are Stellate macrophages?
Stellate macrophages = hepatic macrophages
* Move through sinusoids
* Destroy microorganisms that have made it through intestine and worn out blood cells
How does bile move?
Bile moves from hepatocytes →bile canaliculus →bile duct
What are the anatomical structures of the liver?
- Hepatocytes
- Liver sinusoids
- Central veins
*Stellate macrophages
How does blood travel through the liver?
- Blood in portal arteriole and Blood in portal venule (mix)
- Blood mixes within sinusoid Gives hepatocytes access to oxygen, nutrients, etc
- Blood leaves the lobules through the central veins
on its way to the heart
How do the liver and the gallbladder connect?
- A series of ducts connect liver to gallbladder and duodenum
What is the purpose of the gallbladder?
- Gallbladder stores and concentrates bile
- Bile = cholesterol, bile acids, salts, and bilirubin
What are gallstones?
Gallstones
* Usually formed of cholesterol that precipitates out of bile while stored in gallbladder
how is bile released?
- A sphincter at the duodenum controls the release of bile into the duodenum
What is the purpose of the pancreas?
- Exocrine (digestive) function:
- Acinar cells produce and secrete
pancreatic enzymes/juices
– Breakdown different food types
– Neutralizes chyme (bicarbonate) - Pancreatic juices transported in
main pancreatic duct and released
by sphincter - Hormone controlling the release?
- Secretin (produced by the small
intestine)
Endocrine function of the pancreas?
Pancreas also has endocrine function
* Different cells produce different hormones
- Beta cells produce insulin
- Alpha cells produce glucagon
What is the Mesentery?
- Mesentery: double-
sided serous
membrane that
suspends organs
within cavity - Contains blood
vessels, nerves, fat
What are the disorder of the GI tract?
- Ulcers
- Inflammatory Bowl Disease
- Irritable bowel syndrome
- Celiac disease
What are ulcers?
Ulcers
* Crater-like erosions of the mucosa
* Most occur in pyloric region of stomach or
duodenum
* Used to think ulcers were caused by stress
* Now know they are due to bacterium:
Helicobacter pylori
- Binds to gastric epithelium →induces over-secretion
of acid and inflammation →ulcer
* Treatment: antibiotics
What is the Inflammatory Bowl Disease?
Inflammatory Bowl Disease
* Two types
- Crohn’s Disease (more severe)
– Along entire intestine; primarily in terminal ileum
- Ulcerative colitis (less severe)
– Shallow inflammation large intestine; primarily in rectum
* General characteristics:
- Cramping, diarrhea, weight loss, intestinal bleeding
- Abnormal immune and inflammatory response to bacterial
antigens that normally occur in the intestine
* Can be treated with diet
What is Irritable bowel syndrome?
Irritable bowel syndrome
* Affects large intestine
* Causes unknown (smooth muscle, nervous
system, inflammation…)
* Symptoms: abdominal pain, excess gas,
diarrhea, constipation, mucus in stool
What is Celiac disease?
Celiac disease
* Autoimmune
* Gluten triggers and immune response, damages
villi of small intestine
* Treatment: gluten free diet
