Week 1 (modules 1 and 2)

2 parts of digestive system

GI tract, accessory organs

alimentary canal

Gastrointestinal tract

absorption

digested molecules absorbed from GI tract into the blood

mastication

chewing

secretion vs. defecation

secretion is secreting substance to break down food

intraperitoneal

between the peritoneum- where digestive system lies (mostly)

what separates thoracic and abdominopelvic cavities

diaphragm

dysphagia

difficulty swallowing

peristalsis

involuntary “wave-like” muscle contraction through the digestive system

serous membranes (3 major)

pleura, pericardium, peritoneum

pleura

membrane around each lung

pericardium

membrane around heart

peritoneum

membrane around digestive organs

retroperitoneal organs

adrenal glands, kidneys, ureters, uterus, bladder, rectum, pancreas, abdominal aorta, inferior vena cava

intraperitoneal organs

stomach, liver, gallbladder, spleen, most of small and large intestines, ovaries

small intestines

first and fourth part of the duodenum, jejunum, ileum

large intestines

cecum, appendix, transverse colon, sigmoid colon, upper third of the rectum

cardia of stomach

esophageal portion

fundus of stomach

dome at the top

phylorus of stomach

funnel-shaped end into the small intestine

hard palate

roof of oral cavity, maxilla and palatine bones

soft palate

roof of oral cavity in back without bones

Gastroesophageal Reflux Disease (GERD)

acid reflux, heartburn, stomach acids flows back into esophagus

risk factors of GERD

obesity, spicy foods, smoking, alcohol, coffee, large meals

symptoms of GERD

chest pain, blenching, nausea, bitter taste in mouth

treatments of GERD

tums, acid reducers, proton pump inhibitors

what tissue is lining of stomach

simple columnar epithelium

rugae (gastric folds) on inside of stomach

allows stomach to expand

villi and gastric pits of stomach (microscopic folds)

more surface area for digestion, gastric gland secretions

what part of small intestine receives chyme from stomach and digestive enzymes from accessory organs

duodenum

where does pain occur during appendicitis

RLQ

treatments of appendicitis

antibiotics, appendectomy

mesentary

fold of peritoneum that attaches to intestines and wall of abdomen and keeps them together, maintains position, supplies blood vessels and nerves

gingivae

gums

3 layers of teeth

enamel, dentin, pulp

what does liver produce

bile

purpose of bile

forms bubbles around lipids to enable their transportation

Hepatic

liver

cystic

gallbladder

purpose of pancreas

produces enzymes and hormones

tissue type of oral cavity, pharynx, and esophagus

stratified squamous, keratinized

tissue type of gland and duct

simple cuboidal

where are gastric pits located

epithelial layer of the mucosa

chief cells

secrete enzymes in stomach that break down other macromolecules

parietal cells

make stomach acid (HCl) and intrinsic factor

pepsin

breaks down proteins

gastric lipase

breaks down fats

enteroendocrine cells

releases hormones into blood (gastrin)

HCl

converts pepsinogen to pepsin, kills bacteria

acidity of stomach acid

2.5 average

gastric juice contents

HCl, IF, pepsin, gastric lipase

pancreatic juice contents

bicarbonate, proteases, pancreatic lipase, pancreatic amylase

bicarbonate

neutralized acidic chyme

proteases (chymotrypsinogen and trysinogen)

digests proteins

pancreatic lipase

digests fat

pancreatic amylase

digests starch

bile salts

emulsifies fats

cholesterol

type of lipid

electrolytes

digests starch

bilirubin

byproduct of heme breakdown

what tissue are intestines and stomach

simple columnar, non-ciliated

cephalic phase of digestion

initiated by thought, small, sight, taste of food (NS only)

gastric phase of digestion

begin after bolus reaches stomach (NS and hormonal)

Intestinal phase of digestion

after chyme leaves stomach (NS and hormonal)

enteric NS

within digestive system

2 subtypes of enteric NS

myenteric and submucosal plexuses

circulating hormone (endorcrine)

within and outside of digestive system

kcal

energy per gram from a nutrient

essential nutrients

from diet

nonessential nutrients (stomach)

made by body

gastrin

stimulates gastric juice secretion

ghrelin

stimulates hunger

2 main circulating hormones

ghrelin, gastrin

water-soluable vitamins

no storage in body, exits via urine

fat-soluable vitamins

stored in body, excess can cause health problems

gastrocolic reflex

start to eat = urge to defecate

vitamin B12

requires intrinsic factor

vitamin K

given to newborns to prevent Hemolytic Disease of the Newborn

gastroileal reflex

food gets into one part of stomach = stimulates intenstines

local hormones

remain in digestive system(duodenum)

3 main local hormones

Secretin, Cholecystokinin (CKK), gastric inhibitory peptid (GIP)

secretin

stimulates pancreatic juice secretion

when is insulin released

fed state

what type of processes are involved in fed state

anabolic

what processes are involved in fasting state

glucagon

what hormone is released in fasting state

glucagon

myenteric plexus

gut motility

submucosal plexus

secretions and blow flow

autonomic NS

outside of digestive system

2 subtypes of autonomic digestive system

sympathetic and parasympathetic

sympathetic digestive system

stops digestion

parasympathetic digestive system

promotes digestion

Basal metabolic rate (BMR)

energy needed at reast

total metabolic rate (TMR)

energy used by body including physical activity

mucosa tisue (villi and gastric glands)

epithelium

villi tissue type

simple columnar

submucosa

connective tissue and come glands

muscularis

muscle tissue (involuntary)

how can metabolic rate be measured

using calorimeter or respirometer

cholecystokinin (CKK)

stimulates gallbladder to release bile