| Term | Definition |
|---|
| anabolism | builds amino acids-> muscle, used raw materials to synthesize essential compounds |
| catabolism | breaks down amino acids, decomposes substances to provide energy cells needed to function |
| digestive tract | aka gastrointestinal tract or alimentary canal |
| ingestion | occurs when materials enter digestive tract via the mouth |
| mechanical processing | crushing & shearing; makes materials easier to propel along digestive tract |
| digestion | the chemical breakdown of food into small organic fragments for absorption by digestive epithelium |
| secretion | the release of H2O, acids, enzymes, buffers, and salts; by epithelium of digestive tract; by glandular organs |
| absorption | movedment of organic substances, electrolytes, vitamins, and H2O; across digestive epithelium; into interstitial fluid of digestive tract |
| excretion | removal of waste products from body fluids |
| mesenteries | double sheets of peritoneal membrane; suspended portions of digestive tract w/in the peritoneal cavity by sheets of serous membrane; that connectparietal peritoneum with visceral peritoneum; areolar tissue between mesothelial surfaces; provides an access route to & from the digestive tract; for passage of blood vessels, nerves, & lympatic vessels; stabilize portions of attached organs; prevent intestines from becoming entangled |
| lesser omentum | belly fat; stabilized position of stomach; provides access route for blood vessels and other structures entering or leaving liver |
| falciform ligament | helps stabilize position of liver; relative to diaphragm & abdominal wall |
| major layers of digestive tract | mucosa, submucosa, muscularis externa, serosa |
| mucosa layer | inner lining of digestive tract; is a mucous membrane consisting of - epithelium, moistened by glandular secretions; lamina propria of areolar tissue |
| digestive epithelum | mucosal epithelium is simple or statified; depending on loaction, function, and stresses: oral cavity, pharynx, & esophagus > mechanical stresses, lined by statified squamous epithelium; stomach, small intestine, and most of large intestine > absorption, simple columnar epithelium with mucous (goblet) cells |
| enteroendocrine cells | are scattered among coulumnar cells of digestive epithelium; screte hormones that: coordinate activities of the digestive tract and accessory glands |
| lamina propria | anchors mucosa to submucosa; consists of a layer of areolar tissue that contains: blood vessels, sensory nerve endings, lymphatic vessels, smooth muscle cells, scattered areas of lymphoid tissue |
| submucosa layer | layer of dense, irrergular connective tissue; surrounds muscularis mucosae; has large blood vessels and lymphatic vessels; may contain exocrine glands; secrete buffers & enzymes into digestive tract |
| submucosal plexus | also called plexus of Meissner; innervates the mucosa and submucosa; contains- sensory neurons, parasympathetic ganglionic neruons, sympathetic postganglionic fibers |
| muscularis externa | dominated by smooth muscle cells; arranged in- inner circular layer; outer longitudinal layer; involved in mechanical processing; movement of material along digestive tract |
| sersoa | serous membrane covering muscularis externa; execept in oral cavity, pharynx, esophagus, & rectum; where adventia, a dense sheath of collagen fibers firmly attaches the digestive tract to adjacent structures |
| movement of digestive materials | by muscular layers of digestive tract; consist of viceral smooth muscle tissue; along digestive tract: has rhythmic cycles of activity, controlled by pacestetter cells; cells undergo spontaneous depolarization: triggering wave of contraction through entire muscular sheet |
| peristalsis | movement of food; consists of waves of muscular contractions; moves a bolus along the length of the digestive tract |
| control of digestive function | neural mechanisms; control: movement of material along digestive tract; secretroy functions; motor neurons: control smooth muscle contraction and glandular secretion; loacted in myenteric plexus |
| hormonal mechanisms | at least 18 peptide hormones that affect: most aspects of digestive function; activities of other systems: are produced by enteroendocrine cells in digestive tract; reach target organs after distribution in bloodstream |
| oral mucosa | lining of oral cavity; has stratified squamous epithelium; of cheeks, lips, & inferior surface of tongue - is relatively thin, nonkeratinized, & delicate; inferior to tongue is thin & vascular enough to rapidly absorb lipid-soluble drugs; cheeks are supported by pads of fat and the buccinator muscles |
| labia | also called lips; anteriorly, the mucosa of each cheek is continuous with that of the lips |
| vestibule | space between the cheeks (or lips) and the teeth |
| gingivae | (gums) ridges of oral mucosa; surround base of each tooth on alveolar processes of maxillary bones and mandible |
| tongue | manipulated materials inside mouth; functions of tongue: mechanical processing by compression, abrasion, & distortion: manipulation to assist in chewing and to prepare material for swallowing: sensory analysis by touch, temp, & taste receptors: secretion of mucins and the enzyme lingual lipase |
| parotid salivary glands | inferior to zygomatic arch; produce serous secretion- enzyme salivary amylase (breaks down starches); drained by parotid duct (Stensen Duct)- which empties into vestibule at second molar |
| sublingual salivary glands | covered by mucous membrane of floor of mouth; produce mucous secretion- act as a buffer & lubricant; sublingual ducts (Rivinus ducts)- either side of lingual frenulum; in floor of mouth |
| submandibular salivary glands | within mandibular groove; secrete buffers, glycoproteins (mucins), & salivary amylase; submandibular ducts (Wharton Ducts)- open immediately posterior to teeth- either side of lingual frenulum |
| purpose of digestive system | to breakdown food, absorb nutrients, & eliminate waste |
| 2 categories of digestive system organs | 1) alimentary canal (tube) 2) accessory organs |
| digestive processes | 1. ingestion 2. propulsion 3. mechanical digestion 4. chemical digestion 5. absorption 6. defecation |
| peritoneum | -serous membrane of the abdominal cavity - consists of: visceral & parietal layers; peritoneal cavity with serous fluid; messentery; two serous membranes fused together; provide routes for blood vessels, lymphatics & nerves; holds organs in places, stores fat; peritonitis- caused by ruptured appendix, wound, ulcer, ect |
| mucosa (his notes) | lines lumen from mouth to anus; moist epithelial membrane; major functions- secretion: mucus, digestive enzyme, & hormones; absorption; protection; simple columnar epithelium; Goblet cells- mucus secreting; lamina propria- underlies eithelium, connective tissue, capillaries nourish the epithelium and absorb nutrients, contain lymph nodes (conpose MALT)- important against defense against bacterial |
| submucosa (his notes) | contains C.T., blood & lymph vessels, lymph nodes and nerve fibers- elastic fibers- stretch |
| muscularis externa (his notes) | or just muscularis, responsible for peristalsis, contains circular (inner) and longitudinal (outer), muscles for sphincters along GI tract |
| serosa (his notes) | protective outer layer, visceral peritoneum, replaced by adventitia around esophagus |
| enteric nervous system (ENS) [his notes] | own in-house nervous system, regulates digestive system activities, linked to CNS by afferent fibers, also linked to sympathetic and parasympathetic NS |
| mouth (his notes) | oral or buccal cavity, opening- oral orifice, lined with stratified squamous epithelium<many layers of fat cells>, gums, hard palate, dorsum of tongue are keratinized for extra protection, produces defensins (antimicrobial) |
| lips & cheeks (his notes) | lips (labia), skeletal muscles cover by skin, obicularis oris forms bulk of lips, cheeks- buccinators,vestibule (pouch), red margin (lipstick); transitional zone, keratinized skin meets oral mucosa; poorly keratinized, translucent; no sweat glands or sebaceous glands; labial frenulum, median fold that joins lip to gum |
| palate (his notes) | roof of mouth; hard palate (palatine process), rigid surface, tongue forces food against during chewing; corrugated to increase friction; soft palate- mostly skeletal muscles, uvula, covers nasopharymx during swallowing |
| tongue (his notes) | occupies the floor of the mouth; composed mostly of skeletal muscle; helps form food into a bolus - ball of food that we swallow; speech; intrinsic muscles- confined to tongue, not attached to bone; extrinsic muscles- protrude and retract tongue, move side to side; lingual frenulum- fold of mucosa, secures tongue to the floor of the mouth, limits posterior movements; papillae: 3 types- filiform- white, stiff, gives tongue roughness, fungiform- reddish, contains taste buds, circumvallate- "v" at back of tongue; sulcus terminalis- posterior groove, lacks papillae, bumpy due to nodular lingual tonsils |
| salivary glands (his notes) | produce and secrete saliva; saliva: cleanses the mouth, dissolves food chemically to aid in taste, moistens food and help for bolus, contains amylase to start digestion of starch |
| 3 saliva glands (his notes) | parotid, submandibular, sublingual |
| composition of saliva (his notes) | 97-99.5% water; slightly acidic (6.75-7), can vary; contains amylase, lysozyme, IgA, electrolytes, and even some nitrogenous waste, and growth factors (dogs); also have beneficial bacteria and defensins; production of saliva increases when we eat or even when we think about food, average output ~ 1 to 1.5 L/day |
| halitosis (his notes) | bad breath; caused by bacteria |
| teeth (his notes) | set in sockets (alveoli) fo mandible and maxilla; mastication (chewing); tear and grind food; break into smaller pieces to increase surface area; dentition and dental formula- by age 21, 2 sets of teether; 20 primary deciduous (baby teeth) or milk teeth & 32 permantent teeth (adult teeth); permanent teeth- 8 incisors, 4 canines, 8 premolors, 12 molars |
| crown of tooth (his notes) | above the gum (gingiva); covered with enamel (hardest substance in the body) |
| root of tooth (his notes) | embedded in jawbone; neck- connect crown and root; cementum- gomphosis joint, anchors in socket by periodontal ligament; ginival sulcus- recedes as we age; "long in the tooth" |
| dentin (his notes) | bond-like material; underlies cap; forms bulk of tooth |
| pulp cavity (his notes) | contains vessels, nerves, collectively called pulp; supplies nutrients to the tooth, provides sensation; becomes root canal; apical foramen at the tip |
| root canal therapy (his notes) | inflammation caused blood supply to tooth to be cut off, nerve dies, pulp becomes infected by bacteria |
| tooth and gum disease (his notes) | cavities, calculus, gingivitis, periodontal disease |
| cavities (his notes) | results from demineralization of enamel and dentin; caused by dental plaque; plaque => sugar, bacteria, and debris |
| calculus (his notes) | tarter; calcified plaque |
| gingivitis (his notes) | swelling and separation at sulcus caused by tarter |
| periodontal disease (his notes) | progression of ginigvitis; causes loss of tooth |
| pharynx (his notes) | oropharynx -> laryngopharynx; lined with friction resistant stratified squamous epithelium; 2 layers of skeletal muscles; circular and longitudinal; propel food to esophaugs |
| esophagus or gullet (his notes) | ~ 10" long; collapsed unless food passes through; lined with squamous epithelial mucosae; esophageal hiatus- pass through diaphragm; gastroesophageal spincter- between stomach and esophagus- GERD- heartburn- can lead to esophagitis and esophageal ulcers |
| stomach (his notes) | temporary storage chamber; food is broken down mechanically and chemically to form Acid Chyme- liquified food |
| gross anatomy of stomach (his notes) | 10" long; depending on amoung of food; can hold about 4L of food (usually 2L); rugae, longitudinal folds; greater curvature, convex lateral surface; lesser curvature, concave medial surface; cardiac orifice, food enters, cardiac sphincer or LES; fundus, superior protion, dome-shaped; body, mid portion; pyloris, inferior portion, connected to SI, pyloric, pyloric sphincter |
| microscopic anatomy of stomach (his notes) | wall has 4 tunics; muscularis is modified for mixing and churning of food; linning- simple columnar epithelium composed of goblet cells; produce alkaline mucus; dotted with millions of gastric pits, lead to gstric gladns that produce gastric juice: 4 types: cheif cells- secretes pepsinogen (inactive form); pepsinogen is activated by HCl to form pepsin; also produces lipase; parietal cells- secrete HCl and intrinisc factor (B12), HCl- ph 1.5-3.5, activates pepsinogen and dismantles food; mucus neck cells- produce acidic mucus, functions neot yet known; enteroendocrine cells- releases a variety of hormones, gastrin, histamine, endorphins, serotonin, CCK, and somatostatin; protection of stomach- very acidic environment (100,000x's more than blood)- mucosal barrier, thick coat of bircarb-rich mucus, tight junctions of epithelial cells prevent "leaking", epithelial cells are shed and replaced completely every 3-6 days; gastric ulcers- stress, once thought to be the major cause, now H. pylori |
| small intestine & gross anatomy (his notes) | 90% of digestion and absorption; gross anatomy- ~ 20' long[in cadaver] (8-13' due to muscle tone[in living person]) and 1" in diamerter; 3 divisions: duodenum, jejunum, and ileum |
| duodenum (his notes) | 1st 10" from pyloric sphincter (shortest segment); bile and pancreatic ducts deliver juices here- hepatopancreatic sphincter- valve that contols entry of bile and pancreatic juices; aka Sphincer of Oddi |
| jejunum (his notes) | middle 8' |
| ileum (his notes) | 12' terminal portion; joins LI at the ileocecal valve; messentery suspend jejunum and ileum in lower abdominal cavity; framed by LI |
| microscopic anatomy of small intestine (his notes) | surface area and structural modifications make the SI well adapted for absorbing nutrients; 3 modifications- a. plicae cirulares: circular folds similar to rugae in stomach, deep folds of mucosa and submucosa, cause chime to spiral thru lumen: mix with intestinal juices: slow and allow time for full nutrient absorption; b. villi: finger-like projections, 1mm high, increase surface area, core has a dense capillary bed and lacteals; c. microvilli: form brush border, projections of plasma membrane, increase surface area and contain digestive enzymes that complete the digestion of carbs and proteins |
| histology of the intestinal wall (his notes) | intestinal crypts or crypts of Leiberkuhn; secrete intestinal juices, serves as a carrier for absorption of nutrient from chime, contain Paneth cells- release lysozome; epithelium is replaced every 3-6 days; Peyer's patches- trap bacteria that cross the epithelium and prevent from entering the blood stream; duodenal glands: submocosa, produces an alkaline mucus to neutralize the acid chime |
| large intestine (his notes) | larger in diameter but only 1.5m long; absorbs water and eliminates undigested food (feces) |
| gross anatomy of large intestine (his notes) | tenae coli: "ribbon of the colon", longitudenal muscle layer; reduced to 3 bands, tone cause LI wall to pucker into pocket-like sacs called Haustra; epiploic appendages: small fat-filled pouches of visceral peritoneum, unknow significance; subdivision of LI: cecum- blind pouch, below ileocecal valve, beginning of LI, vermiform appendix: part of MALT: Vestigal (no longer needed as adult): appendicitis; colon- ascending, transverse, descending, sigmoid, hepatic & sphlenic flexures; rectum- rectal valves, 3 transvers folds, stops feces from passing along with gas; anal canal- 2 sphincters, internal AS (invol), external AS (vol); anus- opening to the exterior of the body |
| microscopic anatomy of large intestine (his notes) | no vili or plicae circulares, anal canal: mucosa merger with true skin; lined with squamous epithelium for high abrasion; anal sinus- b/w columns, exude mucus when compressed by feces, aid in emptying the anal canal; hemorrhoidal vein: superficial vein associated with anus and anal column |
| bacterial flora of large intestine (his notes) | ferment carbs, produce acids, gas, vitamine B & K, & keep harmful bacteria in check |
| digestive functions of larger intestine (his notes) | few nutrients reach LI, hold undigested food for 12-24 hrs, main function is to absorb water and vitamins; remove undigested food or eliminate waste |
| imbalance of large intestine (his notes) | diverticulosis- leads to diverticulitis; caused by lack of fiber in the diet; small herniations of the mucosa colon wall; coloscopy & colon cancer; inflammatory bowel disease; diarrhea or constipation |
| defecation reflex of large intestine (his notes) | pressure on the wall of sigmoid colon and rectum cause contraction and anal sphincter to relax |
| liver (his notes) | largest gland, wt ~ 3lbs, most on rt side below diaphragm, functions of the liver: detoxify poisons, synthesize nutrients, cholesterol, ect., store glycogen, vitamins, ect., produce bile; 4 lobes |
| liver lobules (his notes) | hexagonal; size of a sesame seed; hepatocytes- liver cells, arranged around a central vein |
| diseases of the liver (his notes) | hepatitis: bacterial or viral: Hep A.- 32% cases- fecal -> from others feces; Hep. C- kills 10,000 americans annually -> silent killer; Cirrhosis: alcoholism & chronic hepatitis, liver becomes fatty and fibrous due to the regeneration of connective tissue that replaces hepatocytes, scars eventually shrink but obstruct blood flow through portal system- blood finds alternate routes that can not accommodate the voulum of blood- leads to caput medusase |
| bile of liver (his notes) | yellow-green, alkaline solutin, contains lots of substances, bile salts, phospholipids, aid in digestions, functions: emulsifies fat (breaks down fat into smaller fat pieces), produce more bile when fatty foods enter the digestive system, bile salts are recycled; pigments are eliminated, bilirubin: gives feces its brown color; recycles Hb |
| gall bladder (his notes) | stores bile, bile leaves via the cystic duct then flows into the bile duct, gall stones; crystallization of cholesterol; imbalance of bile salts and cholesterol |
| pancreas (his notes) | 1. structure- gland located near stomach - head, body, tail - empties its contents into duodenum- Sphincter of Oddi 2. function- it is both endocrine and exocrine; exocrine: produces digestive juices, contain bicaronates (neutralized acid), digestive enzymes- lipase, amylase, proteases (trypsin); exocrine: Isltes of Langerhans produce insulin (lowers blood sugar) & glucagon (raises blood sugar) |
| purpose of nutrition (his notes) | build cell structures; replace worn out cell parts; synthesis of functional molecules; most are used to produce chemical energy- ATP; energy is measured in calories - amount of heat energy needed to increase the temp of 1g of water 1°C, very small unit of meaurement, nutritionist uses kilocalorie or 1,000 calories |
| nutrition (his notes) | 6 categories: major nutrients: carbs, lipids, proteins; vitamins & minerals; water *essential nutrients- can not be made by teh body: must be consumed |
| nutrient (his notes) | substance in fod that is used by the body for growth, maintenance & repair |
| carbohydrates (his notes) | most are derived from plants: plant -> sunlight -> photosynthesis -> glucose; simple sugars- monosaccharides; polysaccharides- starch, glycogen (animal starch), and cellulose (fiber) |
| uses in the body: glucose (his notes) | major fuel source to make ATP; excess glucose is converted to glycogen or fat |
| dietary requirements for carbs (his notes) | 125-175g of carbs/day; <50/day is consumed, use fat and protein for energy; Americans typically consume 200-300g /day; empty calories: candy & sodas; lack vitamins & minerals; sugar & glycemic index make sugar spike& then store as fats |
| lipids (his notes) | saturated fats- animals & H+ ions; unsaturated fats- 1 or more double bonds |
| uses of fat (his notes) | help absorb fat soluble vitamins; energy; myelin sheaths and cell membranes |
| good fats (his notes) | omega 3 & 3 fatty acids, cold water fish (salmon), olive & vegistable oils |
| fat deposition (his notes) | cushion body organs (holds kindey's in place); insulation; energy reserves; prostaglandins & steroid based hormones |
| dietary requirments for lipids (his notes) | <30% of total caloric intake; unsaturated- good; daily cholesterol ~ 200mg (1 egg) |
| protein (his notes) | complete protein: meet all body's amino acid requirments; legumes (beans), meats, milk |
| uses in the body: protein (his notes) | structural materials- keratin, collagen, ect.; muscle; hormones; enzymes; proteins require all necessary A.A; if one is lacking, the protein can not be made- cant store AA; requires daily intake |
| adequate caloric intake (his notes) | protein will be used as fuel if carbs and fat is not vailable |
| nitrogen balance (his notes) | protein synthesis = protein breakdown; negative nitrogen balance when protein is used to produce energy; positive nitrogen balance in growing children and pregnant women |
| hormonal controls (his notes) | anabolic hormones accelerate protein sysnthesis- growth hormone, sex hormone; glucocorticoids are catabolic |
| dietary requirments for proteins (his notes) | depends on age, sex, size, metabolic rate, and current nitrogen balance; generally .8g/kg of body wt.; ~30g in 1 glass of milk; most Americans eat more protein than needed |
| vitamins (his notes) | most are coenzymes; 2 classes of vitamins; fat soluble and water soluble; fat soluble = A, E, D, K (too much can be toxic to liver); water soluble = B & C (too much and you will pee out or get diarreaha) |
| minerals (his notes) | 7 minerals needed in moderate amounts: calcium, phosphorus,potassium, sodium, chloride, sulfur, & magnesium; make up 4% of body wt: calcium and phosphorus in bone- 75% of that; most minerals are ions in body fluids = electrolytes; dozens other minerals are needed in very small amounts- called trace minerals: toxic in high amounts |
| metabolism (his notes) | anabolic & catabolic |
| anabolic (his notes) | builds; takes small molecules & build & use energy |
| catabolic (his notes) | breakdown; takes large molecules & breaksdown to produce energy |
| cell respiration (his notes) | how our bodies produce energy; cell organell that carry on cell respiration = mitocondira; glucose most readily produces energy; |
| anareorbic respiration steps (his notes) | 1) glycolysis (split glucose) 2) acetol CO.A 3) Kreb's Cycle 4) electorn transport chain <need all 3 of the last steps for oxygen present>: produces 36 ATP's: produces about 100lbs of ATP/day (ADP + P = ATP) |
| anareobic (his notes) | no oxygen (2 ATP's; not efficent) & produce lactic acid as waste products |
| Vit A (his notes) | vision/ deficency causes night blindness (found in orange type fruits, carrots) |
| Vit D (his notes) | deposit calicum & phosphorus to bones/ deficency causes Rickets (found in sunlight & added to milk) |
| Vit E (his notes) | oxidation (found in oils to cut down on scars & stretch marks) |
| Vit K (his notes) | helps the blood clott |
| Vit C (his notes) | antioxident & collagen production/ deficency causes Skruvie (found in cirtius fruits & kiwi) |
| B Vitamins (his notes) | B1- thymine, B2- ribofain, B3- nadcin, B5- pantothenic, folic acid- help get PG, B12- increases energy levels, for red blood cells, & intrinsic factors |
| macrominerals | sodium- salt/ needed for fluid balance, potassium- meats, milk, fruits & veggies/ needed for fluid balance, chloride- needed for fluid balance, calcuim- dairy products & leafy green veggies/ needed for bones, phosphorus- meat, fish, poultry/ needed for bones, magnesium- cardiovascular & immune system health, sulfur- meats, poulty, fish, eggs/ for hair strength/ found in protein molecules |
| trace minerals | iron- for RBC/ organ meats, red meats, fish, poultry, zinc- needed for making protein, sexual health, immune system/ meats, fish, wole grains, iodine- helps regulate growth/ seafood, bread, selenium- antioxident, copper, maganese, flouride- formation of bones & teeth, chromium- works with insulin to regulate blood sugar, molybclenum- part of enzymes |
Combine with other sets
Share on Facebook
Share on MySpace