Term
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Definition
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Term
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Definition
| release of fluid and enzymes into the GI Tract |
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Definition
| - the movement of material along the GI Tract |
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Definition
| the breakdown of ingested food stuff |
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Definition
| the passage of digested food and secretions into the blood and lymph |
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Definition
| the elimination of feces (waste products) |
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Definition
layer that contacts food
- Stratified squamous epithelium at each end, columnar epithelium in the middle |
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Definition
- areolar connective tissue contains many blood and lymph vessels
- contains mucosa associated lymphatic tissue (MALT) |
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Definition
| - thin layer of smooth muscle that helps mix food and secretions |
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Definition
- the inner lining
a. Epithelium
b. Lamina propria
c. Muscularis Mucosae |
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Definition
- areolar connective tissue
- contains the Submucosal (Meissner's) Plexus, part of the Enteric Nervous System that controls the Muscularis Mucosae and secretion of the Mucosa |
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Term
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Definition
- mostly smooth muscle (skeletal muscle at each end)
inner layer has circular fibers
outer layer has longitudinal fibers
- contains the Myenteric (Auerbach's) Plexus, the part of the Enteric Nervous System that controls motility through the GI Tract |
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Definition
| Successive muscular contractions along the wall of hollow muscular structures. |
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Definition
- outer most layer
- is known as the Visceral Peritoneum for the portion of the GI Tract that lies below the Diaphragm |
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Definition
| the largest serous membrane in the body, consists of the Visceral and Parietal layers. The serous fluid filled space between these layers is called the Peritoneal Cavity |
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Term
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Definition
| the largest serous membrane in the body, consists of the Visceral and Parietal layers. The serous fluid filled space between these layers is called the Peritoneal Cavity |
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Definition
| A large fold of peritoneum that drapes over the Transverse Colon and Small Intestine. Is mostly adipose tissue and lymph nodes. |
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Definition
| A peritoneal fold that attaches the Small Intestine to the posterior wall of the abdomen. Blood and lymphatic vessels(Lacteals) are contained within this structure |
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Definition
| A peritoneal fold that attaches the Small Intestine to the posterior wall of the abdomen. Blood and lymphatic vessels(Lacteals) are contained within this structure |
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Term
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Definition
| A peritoneal fold that attaches the Large Intestine to the posterior wall of the abdomen. |
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Term
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Definition
| A disorder associated with the accumulation of excess fluid in the peritoneal cavity. |
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Term
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Definition
| A disorder associated with the acute inflammation of the peritoneum. A ruptured appendix is the most common cause. |
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Definition
Oral Cavity = Buccal Cavity
- the beginning of mechanical and chemical digestion
- contains 32 permanent teeth
- Mastication = chewing - cut and grinding of food into smaller particles |
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Term
| 3 pair of Salivary glands |
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Definition
| (Parotid, Submandibular and Sublingual) which secrete saliva (~99.5% water), also contains urea, uric acid, lysozyme (a bacteriocide), salivary amylase, lingual lipase and various ions. These normally secrete 1 - 1 1/2 liters of saliva per day. |
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Term
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Definition
| the mass of food produced from oral digestion |
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Term
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Definition
| swallowing - the movement of food from the mouth to the Stomach. Deglutition is initiated when the Bolus of food is forced into the Oropharynx. After the initial stage the rest of swallowing is usually an involuntary response. Respiration is temporarily suspended. |
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Term
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Definition
| lower esophageal sphincter - this relaxes as food is moved towards the Stomach |
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Term
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Definition
| the opening in the Diaphragm for the Esophagus |
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Term
| Gastroesophageal Reflux Disease (GERD) |
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Definition
| - Acidy stomach contents move past the Cardiac sphincter into the lower Esophagus producing "heart burn". In extreme cases this reflux can lead to cancer. Treated by avoiding acid producing foods and acid reducing medicine. |
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Term
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Definition
| controls the passage of digested food (chyme) into the Small Intestine. |
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Term
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Definition
| columnar cells that secrete mucous, these line the lumen of the Stomach |
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Term
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Definition
| invaginations of mucosal cells into the Lamina Propria |
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Term
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Definition
| collections of various secretory cells located at the bottom of Gastric pits |
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Definition
- mucous secreting cells that have some absorption capabilities (ex. water, ions, short fatty acids, aspirin, alcohol)
- these coat and protect the Stomach wall |
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Term
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Definition
- secretes pepsinogen which is converted into the proteolytic enzyme pepsin. Pepsinogen is activated by hydrochloric acid or active pepsin. Pepsin is most effective around pH 2.
- also secretes Gastric lipase |
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Term
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Definition
- Secretes HCl which denatures protein, kills microbes and activates Pepsin
- Secretes Intrinsic Factor which attaches to B12, this allows B12 to be absorbed in the Small Intestine
(Re: Pernicious Anemia) |
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Term
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Definition
- mostly located in the Pylorus (distal Stomach), and secrete the hormone Gastrin into the blood
- Gastrin stimulates Chief and Parietal cells, causes the Cardiac sphincter to constrict, increases the churning of Stomach muscles and relaxes the Pyloric sphincter. |
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Term
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Definition
- Stimulated by sight, smell, taste, and thought.
- Initiates the secretion of gastric cells and stimulates smooth muscle activity (through CN 10, Vagus Nerve). |
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Term
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Definition
- Initiated by both neural and hormonal mechanisms
- Stretch and chemoreceptors for pH initiate gastric secretions and the mixing waves in the Stomach.
- Small amounts of chyme are periodically released into the Small Intestine as the result of muscular contractions.
- Gastrin is released by distension of the Stomach, partially digested protein and caffeine. |
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Term
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Definition
| - This tends to slow the release of chyme from the Stomach, promoting complete digestion and absorption. Hormonal and neural mechanisms exist. |
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Term
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Definition
- Released when highly acidic chyme enters the Duodenum.
- Promotes bicarbonate ion secretion (raising pH) in the Pancreas and bile. |
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Term
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Definition
- Released when partially digested proteins, triglycerides and fatty acids enter the Duodenum.
- Promotes the secretion of pancreatic juice. Causes the constriction of the Pyloric sphincter (slowing the release of chyme). Causes the contraction of the Gall Bladder(releasing bile). Induces satiety (a feeling of fullness). |
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Term
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Definition
| Clusters of cells that produce pancreatic enzymes. Acini account for approx. 99% of the Pancreas (exocrine), the rest being Pancreatic Islets(endocrine). |
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Definition
- Mostly water, also contains bicarbonate ions and enzymes.
- Enzymes:
(1) Pancreatic Amylase for CHO digestion.
(2) Proteases
- Trypsin, Chymotrypsin, Carboxypeptidase, Elastase
(3) Pancreatic lipase for lipid digestion.
(4) Nucleases
- Ribonuclease, Deoxyribonuclease |
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Term
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Definition
- Both neural and hormonal mechanisms exist.
- Secretion is initiated by the Cephalic and Gastric phases of gastric digestion, and when acidic chyme enters the Duodenum. |
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Term
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Definition
(1) Hepatocytes produce a slightly alkaline bile (to emulsify fats).
(2) Carbohydrate metabolism
- Storage of glycogen
- The breakdown of glycogen into glucose.
- The conversion of lactic acid and amino acids into glucose.
(3) Lipid metabolism
- Triglyceride storage
- Cholesterol synthesis, production of hormones and bile salts.
(4) Protein metabolism
- Deamination of amino acids
- Produce urea
(5) Detoxify drugs and hormones.
(6) Excretion of biliruben in the bile.
(7) Storage of vitamins and minerals.
(8) Phagocytosis of blood cells and pathogens by Kupffer's cells.
(9) Synthesis of Vitamin D. |
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Term
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Definition
- Storage of glycogen
- The breakdown of glycogen into glucose.
- The conversion of lactic acid and amino acids into glucose. |
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Definition
- Triglyceride storage
- Cholesterol synthesis, production of hormones and bile salts. |
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Definition
- Deamination of amino acids
- Produce urea |
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Term
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Definition
| - A muscular sac, 3 to 4 inches long, that lies on the inferior surface of the Liver. Stores and concentrates bile. |
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Term
| Circular Folds (Plicae Circularis) |
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Definition
| - Structures on the mucosal surface that cause chyme to spiral through the Small Intestine. This promotes digestion and absorption. |
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Term
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Definition
- Finger-like projections of the mucosa into the lumen.
- Contains lacteals, arterioles and venules. |
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Term
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Definition
| - Cytoplasmic projections on the apical surface of epithelium. (these form the "Brush Border" appearance of the Small Intestine) |
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Definition
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Term
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Definition
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Definition
| Secrete lysozyme (antibacterial) |
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Term
Duodenal (Brunner's) glands
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Definition
| Secretes alkaline mucous (neutralize acid). |
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Term
| Peyer's Patches and other lymph structures |
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Definition
| - Are most concentrated in the distal Ileum. |
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Term
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Definition
| - Slightly alkaline fluid secreted by mucosal cells that contains various digestive enzymes. |
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Term
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Definition
| - Localized mixing contractions that occurs in distended portions of the Small Intestine. This mixes chyme with digestive juices and helps bring nutrients into contact with the muscosa. |
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Term
| Migratin Motility Complex = |
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Definition
Peristalsis
- propelling chyme towards the Ileocecal valve |
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Term
Absorption in the Small Intestine:
Carbohydrates |
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Definition
- absorbed as monosaccharides
- transported in the blood |
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Term
Absorption in the Small Intestine:
Protein |
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Definition
- Absorbed as amino acids, dipeptides and tripeptides. Peptide bonds are broken inside of mucosal cells.
- Transported in the blood. |
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Term
Absorption in the Small Intestine:
Lipid |
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Definition
- Bile salts cause large "globs" of lipid to become smaller structures called Micelles.
- Fatty acids, monoglycerides, glycerol, fat soluble vitamins and cholesterol are absorbed into mucosal cells.
- Mucosal cells form new triglycerides. These cells produce a structure called a Chylomicron, a structure with a lipid center that is surrounded by protein. Chylomicrons are released into lacteals.
- Short chain fatty acids are transported in the blood. |
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Term
| Movements of the Large Intestine |
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Definition
(1) Peristalsis
(2) Haustral Churning
- Haustra fill then contract to move contents forward.
(3) Mass Peristalsis
- A single, strong peristaltic wave that begins in the Transverse Colon, and sweeps feces toward the Rectum.
- This reflex is initiated when Gastrin is first released during the Gastric Phase of Gastric digestion. |
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Term
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Definition
| - Haustra fill then contract to move contents forward. |
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Term
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Definition
- A single, strong peristaltic wave that begins in the Transverse Colon, and sweeps feces toward the Rectum.
- This reflex is initiated when Gastrin is first released during the Gastric Phase of Gastric digestion. |
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Term
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Definition
- Bacteria ferments the remaining nutrients releasing gases (flatus), some vitamins are produced.
- Water, vitamins, and electrolytes are absorbed as they come into contact with mucosal cells. |
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Term
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Definition
Defecation
- Distension of smooth muscle fibers initiates the defecation reflex.
- Skeletal muscle fibers provide voluntary control. |
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Term
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Definition
| - Increased frequency and volume of feces caused by increased motility and/or decreased absorption. This can lead to increased fluid and electrolyte imbalance. |
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Term
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Definition
| - Increased frequency and volume of feces caused by increased motility and/or decreased absorption. This can lead to increased fluid and electrolyte imbalance. |
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Term
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Definition
| - Infrequent and/or difficult defecation caused by decreased motility. This leads to excessive water absorption. This can be caused by poor bowel and bladder habits, lack of exercise, stress, drugs. |
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Term
| Dental Caries = Tooth decay |
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Definition
| - Gradual demineralization of enamel and dentin due to microbial activity. Bacteria convert sugars into acids which facilitates this process. |
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Term
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Definition
- A crater like lesion that forms in areas exposed to gastric juice. This can lead to bleeding and anemia.
- Helicobacter pylori is the most common cause. This bacteria causes ammonia to form which neutrilizes stomach acid._ |
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Term
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Definition
| - Can also be caused by NSAID (non-steroidal anti-inflammatory drug) therapy, and over secretion of acid. |
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Term
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Definition
- Inflammation of diverticuli.
- Diverticuli = An out pouching of the wall of the intestine.
- Causes pain, nausea, vomiting.
- Often caused by low dietary fiber intake. |
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Term
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Definition
- The is often a genetic component exacerbated by chronic irritation (ex. low fiber diet), alcohol, or a diet high in protein and fat.
- This disorder can lead to changes in bowel or bladder habits, abdominal pain, rectal bleeding (overt or occult), ribbon like stools. |
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