Digestive & Urinary System
Isabel Garcia, period:1
Major functions of the digestive system
Major functions of the urinary system
Major organs of the digestive system
Major organs of the urinary systems
Digestive enzymes (including names and functions)
Location of digestion and absorption of each macromolecule
Layers of the GI tract (including stomach)
Nephron anatomy and physiology
Disorders of the digestive and urinary systems
The major function of the digestive system is:
-taking in food -breaking food down into nutrient molecules
-absorb molecules into bloodstream -rid body of any indigestible remains
Also known as the alimentary canal, breaks down food
Organs included are mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus
Mouth: walls are stratified squamous epithelial, soft palate closes nasopharynx when swallowing, saliva contains enzymes to break down food
Tongue: gripping, repositioning, and mixing food while chewing, creates bolus (food & saliva), initiation of speech, swallow, and taste
Salivary Glands: function of saliva is to cleanse mouth, dissolve food chemicals for taste, moisten food; contains serous (watery secretion, enzymes, ions, mucin) cells, and mucous (mucus) cells
involves ingestion, propulsion, mechanical breakdown, digestion, absorption, and defecation
Mucosa: tunic layer that lines lumen, and functions in: secreting mucus, digestive enzymes, and hormones; absorbing end products of digestion; protect against infectious disease
Submucosa: contains blood and lymphatic vessels, lymphoid follicles, and submucosal nerve; has alot of elastic tissue to help organs regain shape after eating
Muscularis externa: responsible for segmentation & peristalsis, contains inner circle muscle layer and outer longitudinal layer
Serosa: outermost layer, makes up the visceral peritoneum
Digestive organs have Peritoneum, which is a serous membrane that consist of visceral (External surface) and parietal (lines body wall)
Saliva contains amylase to begin breakdown with starch
Pancreatic juice contains:
-Proteases (proteins) -Amylase (carbohydrates) -Lipases (lipids) -Nucleases (nucleic acid)
Small intestine also have brush border enzymes to further break down the food that passes
Esophagus: collapsed tube (when no food propulsion) that goes from laryngopharynx to stomach
Stomach: starts chemical breakdown of protein digestion, converts bolus into chyme, contains gland cells which produces mucous neck cell (acidic mucous) & parietal cells (Hydrochloric acid & intristic factor)
Pancreas: supplies enzyme needed to digest chyme and bicarbonate to neutralize acid; secretes insulin and glucagon
Liver: produces bile
Gallbladder: chief storage of bile
Small Intestine: major for digestion and absorption; villi contains fingerlike projection, microvilli contain enzyme for final carbohydrate and protein digestion
Large Intestine: contains teniae coli (3 bands of longitudinal smooth muscle), haustra (pocketlike sacs), and epiploic appendages (fat-filled pouches)
Residue remains 12-24 hours, propulsion of feces to anus and defecation
Re-absorption of vitamins, water, and electrolytes
Proteins: digestion occurs in the stomach and small intestine;
pepsin is first used to break down followed by pancreatic enzymes to create small polypeptides and small peptides to finally amino acid by the brush border enzyme
amino acid are absorbed via cotransport with Na+; dipeptides & tripeptides absorbed via cotransport with H+
Lipids (Fat): breakdown occurs in mouth, stomach, and small intestine
lingual and gastric lipase is used to breakdown, then by emulsification using bile from liver, then pancreatic lipase
Nucleic Acids: digestion occurs in small intestine
pancreatic ribo-nuclease & deoxyribonuclease break down the nucleic acid, then brush border enzymes break it down further to pentose sugars
units enter intestinal cells active transport via membrane carriers
Carbohydrate: digestion occurs in mouth and small intestine,
salivary amylase is used to break down starch, then pancreatic amylase
brush border enzymes then break down lactose, maltose, and sucrose and all the following
glucose and glactose are absorbed via cotransport with Na+
Creates urine through kidneys through the flow Renal pyramid →minor calyx →major calyx →renal pelvis →ureter
Kidneys also filters blood and adjust its compostition
Kidneys: regulates total water volume & solute concentration in water
regulate ion concentration in ECF; excretes metabolic waste, toxins, drugs; produces erythropoietin; activates Vitamin D,
Ureter: carries urine from kidneys to urinary bladder
Urinary bladder: temporary storage reservoir for urine
Functional units that forms urine in kidneys; two main parts are i. renal corpuscle & ii. renal tubule
i. contains
Glomerulus: tuft of capillaries composed of fenestrated endothelium; allows for efficient filtrate formation
Glomerular capsule: hollow structure surrounding glomerulus; consist of parietal and visceral layer
ii. consist of single layer of epithelial cells, consist of
Proximal convoluted tubule (PCT) [closest to renal corpuscle]: cuboidal cells with dense microvilli that form brush border; functions re-absorption and secretion
Nephron loop [Loop of Henle]: U-shaped consisting of descending limb & ascending limb
Distal convoluted tubule (DCT): cuboidal cells with few microvilli; function in secretion rather than re-absorpition
Collecting Duct consist of principle and intercalated cells
Glomerular filtration: forces fluid and solutes through filtration membrane
Tubular reabsorption: reclaims most of tubular contents & returns them to blood
Tubular secretion: reabsorption in reverse
^important for disposing of substances (drugs/metabolites), eliminating undesirable substances, riding body of excess K+, controlling blood pH
Cholecystitis: redness and swelling on gallbladder, occurs when bile is trapped in gallbladder; Symptoms: sudden pain, nausea, vomit, fever
Treatment: Antibiotics or surgery
Gastroesophageal Reflux Disease (GERD): acid flows back up the esophagus; Symptoms: chest pain, difficult swallowing, burning sensation
Treatment: Antacid, proton-pump indicator, Bariatric surgery
Inflammatory Bowel Disease (IBD): chronic inflammation in digestive tract; Symptoms: diarrhea, fatigue, abdominal pain
Treatment: immunosuppressive drugs to reduce inflammation
Peptic Ulcers: open sores on inside of lining of stomach; Symptoms: burning stomach pain, bloating, heart-burn, nausea
Treatment: medication to decrease stomach acid production
Colon Diseases: infection; Symptoms: abdominal pain, cramping, fever
Treatment: antibiotics
Bladder Cancer:
Urinary Tract Infection (UTI): infection; Symptoms: persistent urge to urinate, burning sensation, cloudy urine
Treatment: antibiotics
Kidney Stones: hard deposits of minerals and salt forms; Symptoms: sever sharp pain in back and side, pain in burning sensations, nausea
Treatment: extracorporeal shock wave lithotripsy (ESWL), surgery, lots of water