DIGESTIVE SYSTEM
http://www.youtube.com/watch?v=Z7xKYNz 9AS0 http://www.youtube.com/watch?v=qyJx_UVE gQI&feature=related
Extends from mouth to anus, and consists of the oral cavity, pharynx, esophagus, stomach, small intestine, and colon. Where does digestion take place?
Teeth Tongue Salivary glands Liver Gallbladder Pancreas
Enamel: Dentin: Pulp cavity: Periodontal membrane: Crown: Root:
Made of: Nerves: Papillae Swallowing: Step 1: Step 2:
Salivary glands: Salivary amylase: Lysozyme:
Food movement Reflex: _______________ Swallowing: Pharynx constricts Breathing pauses Soft palate elevates to block nasopharynx Larynx elevates Epiglottis closes Esophagus starts peristalsis
Peristalsis LES (lower esophageal sphincter) or cardiac sphincter
Mucosa: Location: Function: Submucosa: Location: Function: External muscle layer: Location: Function: 2 layers:_____ & ______ Serosa: Location: Function:
Visceral Peritoneum Parietal Peritoneum Mesentery
http://www.youtube.com/watch?v=SKP1qxpooo
Location: Structure: Function:
Cardiac orifice Fundus, Body, Pylorus Rugae External muscle layer Pyloric sphincter Chyme
Gastric pits Mucous cells Chief cells Parietal cells G cells Histamine Proton pumps
H2 receptors
Duodenum Jejunum Ileum Peyers patches Peristalsis Ampulla of Vater
http://www.youtube.c om/watch?v=xu5jDCX 2cHM
Digestive secretions: 3 sources Liver Pancreas Duodenum Secretin Bile
Villi vs. Microvilla Structure: Function: Villi: Capillary network Lacteal (lymph capillary)
Hepatocytes Liver lobules Hepatic duct Cystic duct Common bile duct Portal vein Hepatic vein http://www.youtu be.com/watch?v=t at0QYxlCbo Digestive function: Bile production
Bile Made by: Stored: Function: Composition:
Produces & excretes bile Glucose/Carbohydrate metabolism Amino acid metabolism deanimation
Lipid metabolism Synthesis of plasma proteins Bilirubin formation Phagocytosis (Kupffer cells) Storage Detoxification ETOH & meds Ammonia
2 functions: 1. 2.
When needed, contracts to propel bile to the duodenum
Exocrine Produces pancreatic juice made of: 1. Bicarbonate
Function:
2. Digestive enzymes
Pancreatic duct Common bile duct
Digestive enzymes: Protease (i.e.Trypsin) Amylase Lipase
Functions: Structure: Ileocecal valve Cecum Appendix Purpose: Ascending, Transverse, Descending Sigmoid Rectum, Anal canal, Anus
Normal Flora Haustra Goblet cells
Anal canal Anus Internal anal sphincter: ________muscle Relaxes as part of the defecation reflex External anal sphincter: _________muscle _________ control
Sense of taste Saliva Reduced secretions LES loss of muscle tone Sluggish peristalsis Gallstones, cholecystitis
TEMPERATURE & METABOLISM
Normal range - 96.5-99.5 f Average = 98.6 f Fluctuates 1 to 2 f in 24 hour period Lowest temp during sleep The very young and the very old
Thyroxine Epinephrine Active organ Food intake Fever
SkinOthers: Respiratory tract Urinary tract Digestive tract
Radiation Conduction Convection Vasoconstriction Vasodilation Sweating
Hypothalamus Mechanisms to increase heat loss Mechanisms to conserve heat
Temperature above 99.5 fHypothalamus Pyrogens
Purposes of fever: 1. 2.
Sum of all chemical reactionsAnabolism Catabolism
Cell respiration
C6H12O6 + O2 => CO2 + H2O + ATP + heatGLUCOSE BREAKDOWN: 3 STAGES 1. Glycolysis
2. Krebs citric acid cycle 3. Cytochrome (electron) transport system
Location: Input : glucose & ATP investment No O2 needed yet Changes (1) glucose to (2) pyruvic acid Output: pyruvic acid, ATP, high energy electrons & H+ (carried by NADH), heat
If NO O2:
pyruvic acid is converted to lactic acid
If O2:
pyruvic acid continues to the next stage, Krebs cycle
Location: Input: pyruvic acid & oxygen Others: Converts each pyruvic
acid molecule into 3 carbon dioxide molecules (one carbon each)
Output: CO2, ATP, high energy electrons & H + (carried by NADH & FAD)
Location: Input: O2, electrons & H+ Also need: Transfers the energy that was released in the form of high energy electrons to ATP. Output: ATP, H20 Most of the ATP comes from this stage
Proteins: made of AMINO ACIDS Extra amino acids DEAMINATED by liver, then converted into pyruvic acid, acetyl CoA, or ketones Goes directly into Krebs cycle
Fats: made of GLYCEROL & FATTY ACIDS Can also be broken down by liver into pyruvic acid, acetyl CoA, or ketones Goes directly into Krebs cycle
KETONES & KETOSIS
calorie: Kilocalorie (Calorie with a capital C) 1 gram FAT = 9 KILOCALORIES 1 gram CARBOHYDRATES = 4 KILOCALORIES 1 gram PROTEIN = 4 KILOCALORIES
GLUCOSE Used to build pentose sugars (DNA & RNA) Extra: Energy stores: Glycogen
PROTEINS: AMINO ACIDS Used to build amino acids not obtained in diet by liver Used by tissues to build proteins Hormones Antibodies Collagen Myosin & actin Clotting factors Many more!
FATS: FATTY ACIDS & GLYCEROL Used to make phospholipids cell membranes Used to make cholesterol: Cell membranes Steroids (ie. Cortisol,
estrogen) Bile salts
Extra: stored as fat in adipose tissue
Amount of heat production Contraction of muscles Contraction of heart muscle Breakdown of cellular components
The energy required for merely livingEnergy at rest
Exercise Age Body configuration of adults Sex hormones Sympathetic stimulation Decreased food intake Climate
Metabolic rate decreasesSensitivity to external temp changes
