Ailementary Canal : (Not Part of Your Body)

DIGESTIVE SYSTEM Ailementary Canal : (not part of your body) mouth -> pharynx -> esophagus -> stomach ->(duodenum -> jejunum -> ilium) -> teeth liver ------Small Intestine------tongue Accessory organs gal bladder salivary glands pancreas cecum ->( ascending colon -> transverse colon -> descending colon -> sigmoid) -> appendix —(going up)------Large Intestine------(going down)------rectum -> anus

* Salivary Glands - produce 1 liter of saliva a day -> have ducts - - some glands have ducts...... some don’t - (sweat glands) - (lymph glands) (thyroid glands) (endocrine glands)

3 sets of Glands 1. parotid gland : inferior and beneath the ear -duct comes in on cheek. 2. submandiblar gland : underneath and in front of the tongue 3. sublingual gland: back and underneath of tongue

chew food -> now called Bolus - you swallow Bolus

functions of Saliva - breakdown of carbohydrates - lubrication - solvent - speech - buffering agent - neutralizes - excretes bacteria

3 phases of secretion of saliva 1. psychic phase - you think about food (smell) (drooling) 2. buccal phase - food is in mouth ( secreting saliva) 3. esophageal phase - to wash everything down * Pharynx : strong muscle used to swallow ( back of throat) - move food BOLUS to stomach

* Esophagus : collapsible tube - posterior of trachea ad heart

striated muscle ------> smooth muscle (voluntary) (involuntary)

- peristalsis : in and down contraction

-when cardiac or esophageal sphincter breaks down - heart burn or puke can cause long term problems in esophagus

- Classroom demo ..... Saltines crackers ( if you can regurgitate well....you have strong esophageal muscles)

* Stomach - stretchable organ Fundus Body Pyloris Pyloric Sphincter - pylorospasm - food can’t leave the stomach thus vomit (infants)

-Functions of the Stomach- 1. churn (mix) food 2. absorbs water and drugs 3. storage

- It takes 2-6 hours for stomach to empty -

* 3 main groups of cells* 1. Chief Cell - produce various gastric juices

2. Parietal Cell - produces HCL Intrinsic factor H + Cl combine in stomach

3. Goblet Cell - produces mucus

- Rennin produced coagulates milk otherwise it’s too liquidy; common in young

3 Ways to Prevent Self Digestion 1. produce mucus 2. epithelial cells had tight juncture 3. epithelial cells replace themselves every three days 10% males 4% females Drugs can effect this & cause ulcers

* 3 Phases of Digestion *

1. Cephalic Phase: - 30 % of gastric juices of enzymes are secreted in this phase - secretion & motility - when you expect food

2. Gastric Phase: where 70 % of gastric juices are secreted. -> (one of the juices: gastrin) -> causes increase in secretion -> cause increase in motility

3. Intestinal Phase: - CCK-PZ from intestine goes to stomach to slow digestion especially with fats

Digestion Speed: * Slow : Fats -> Lipase -> fatty acids

* Fast : Carbohydrates -> Polysaccharide -> Disaccharides -> Monosaccharides

* In Between: Protein -> Protease -> Peptides -> Amino Acids

* Small Intestine: 20 feet long - first 10in. = duodenum (Shaped like a “C”) - second 8 feet = jujunum - third 12 feet = ilium

- Chyme goes out of your stomach -> moves through your body - called segmentation (not peristalsis)

* folds on, folds on, folds on, folds on, folds on, folds on...... * - triple folded - increase surface area. Folds on fold in small intestine - villi

Triple fold - microvilli - brushborder

Brunner’s Gland: secretes two things 1. mucus- to protect the intestines from acids 2. NaHCO (Sodium bi-carbonate) - it neutralizes acids enzymes in intestines-> ph of 7 (neutral) - environment where enzymes work best.

* 5 brush border Enzymes * 1. maltase: maltose -> sacrose 2. sucrase: glucose -> sucrose 3. Peptidases: pepsin (smaller) 4. Lipase: lipids 5. Lactase: lactose ( lose when you age)

* Liver - exocrine gland ( has ducts) (today - we can only transplant exocrine glands) - weighs- 3-4 lbs

* functions of the liver* 1. detoxify substances in blood 2. produces bile (pint a day) 3. stores iron, vitamin A, B12, & D 4. metabolizes food in blood

- Bile - is green because of pigment biliverdin from hemoglobin - stored in conc. In gal bladder if conc. Is too high -> Gal Stones

Porta Hepatica-

Portal System - 4 lobes : Right Proper Caudate Quadrate Left

- jaundice - you’re bile ducts are blocked and bile is absorbed into blood Feces becomes grey Blood and skin yellow

Bile - is not an enzyme - cholesterol - builds up cell membrane and some hormones - breaks down fats so lipase can work quicker ( like soap) 2 types: good - monosaturated (double carbon bonds) bad - saturated (carbon-hydrogen bonds) solid at room temp (Animals)

* Pancreas - 12-15 cm long - “arms” of the duodenum - weighs 60 grams

2 functions of the pancreas - endocrine - produces insulin (used for blood sugar) ....diabetics (ductless) - exocrine - (ducts) leads to small intestine (duodenum) 1. NaHCO (Sodium bicarbonate) 2. pancreatial amylase : breaks down starches

- Pancreatitis- inflammation of the pancreas

* Large Intestine - 5-6 Feet - 2 ½” diameter

* Functions of the Large Intestine* - absorbs water - forms feces - home to bacteria Problems with the large intestine: 1. Constipation - * heathy person - goes poop 2-3 times a day 2. Diarrhea - where absorption of water is not occurring 3. Colon Cancer 4. Hemorrhoids - tissue near anus becomes inflammed and bleeds -common - older men (they push to hard when pooping or sit to long) - girls (when pregnant)

A- illium B- cecum C- appendix D- ascending colon E- transverse colon F- descending colon G- sigmoid colon H- rectum I- anal sphincter J- anus L- taenia coli K- haustra (bumps, ridges) M - mesocolon

- peritoneum - connective tissue that keeps organs in place - Greater Omentum - flap of fat (beer belly).....connective tissue also

* Urinary (excretory) System - - size of a lima bean - just above waist line A- kidney B- adrenal gland C- inferior vena cava -> main vein in the abdomen (leads to the heart) D- descending aorta E- renal vein F- renal artery G- ureter H- bladder I- urethra

* functions of the kidneys* 1. to get rid of nitrogen wastes 2. to rid the body of toxins 3. regulates water

Problems: 1 - kidney stones: build up of nitrogen wastes 2 - bladder or kidney infections - more common in females