The Digestive System

Front 1

List the organs of the GI tract

Back 1

larynx, esophagus, stomach, small intestine and large intestine

Front 2

a continuous tube that extends from the mouth to the anus

Back 2

alimentary canal

Front 3

how long is the alimentary canal in a cadaver?

Back 3

30 feet

Front 4

anything found within this part of the GI tract is technically still external to the body

Back 4

lumen

Front 5

what must the contents of the GI tract come across to come into the body?

Back 5

epithelial lining

Front 6

what accessory organs of the GI tract are considered physical breakdown organs?

Back 6

teeth and tongue

Front 7

what accessory organs of the GI tract are considered secretory organs?

Back 7

pancreas, liver, gallbladder, and salivary glands

Front 8

secretory organs produce or store secretions that will reach the digestive tract via what?

Back 8

ducts

Front 9

the taking of food and liquids into your mouth; eating

Back 9

ingestion

Front 10

cells within the wall of the GI tract and secretory accessory organs secrete approximately how much water, HCl, digestive enzymes, buffers and mucous into the GI tract lumen every day?

Back 10

7 liters

Front 11

the GI tract has ___________ _____________ meaning that it can mix whatever is found in the lumen portion of the GI tract and push it along

Back 11

motility capability

Front 12

alternating contraction and relaxation of the smooth muscle that helps mix the food with secretions and propel it through the GI tract from proximal to distal

Back 12

peristalsis

Front 13

the physical breakdown of food

Back 13

mechanical digestion

Front 14

when we take very large macromolecules and split them into smaller molecules through hydrolysis using digestive enzymes

Back 14

chemical digestion

Front 15

List the things that can be absorbed across the epithelial lining without being broken down.

Back 15

vitamins, ions, some cholesterol, and water

Front 16

what things in our body produce digestive enzymes?

Back 16

salivary glands, tongue, pancreas, small intestine, stomach

Front 17

the entrance of substances across the epithelial lining and into the body

Back 17

absorption

Front 18

where does 90% of absorption take place?

Back 18

small intestine

Front 19

the things that don't make it across the epithelial lining leave the body through this process

Back 19

defacation

Front 20

the elimination of material including waste products, indigestible substances, bacteria, sloughed off cells from the GI tract lining, and materials that were never absorbed

Back 20

defacation

Front 21

the inner lining of the GI tract that serves as a line of defense

Back 21

mucosa

Front 22

this is one function of the GI tract; within the wall of the GI tract in certain areas you can find lymphatic tissue that serve's as the body's first line of defense if anything is absorbed that can be dangerous such as an antigen

Back 22

immunological protection

Front 23

how many abdominopelvic quadrants are there?

Back 23

4

Front 24

what quadrant is the vermiform appendix in?

Back 24

right lower quadrant

Front 25

what quadrant is the spleen in?

Back 25

left upper quadrant

Front 26

innermost layer of the GI tract

Back 26

mucosa

Front 27

the mucosa is composed of a lining of ____________________ with underlying ____________ ____________________

Back 27

epithelium, connective tissue

Front 28

what are the 3 principle functions of mucosa?

Back 28

protection, absorption and secretion

Front 29

this layer of the GI tract surrounds the mucosa

Back 29

submucosa

Front 30

layer of loose connective tissue that binds mucosa to the muscularis externa

Back 30

submucosa

Front 31

what things can the submucosa contain?

Back 31

glands, vessels, lymphatic tissue and nerves

Front 32

this layer of the GI tract contains smooth muscle cells

Back 32

muscularis externa

Front 33

what nervous system controls the muscularis externa?

Back 33

autonomic nervous system

Front 34

this layer helps to mechanically break down food, mix it with digestive secretions and move it through the GI tract from proximal to distal

Back 34

muscularis externa

Front 35

the smooth muscle cells of muscularis externa are organized into what 2 sheets?

Back 35

inner circular fibers and outer longitudinal fibers

Front 36

when these muscles contract, the diameter of the lumen becomes smaller, but the organ lengthens

Back 36

inner circular fibers

Front 37

when these muscles contract, they open the lumen up and shorts the organ

Back 37

outer longitudinal fibers

Front 38

thickening of the circular muscular layer along the GI tract results in what?

Back 38

sphincters or valves

Front 39

this sphincter is found between the stomach and small intestine

Back 39

pyloric sphincter

Front 40

there is a third layer of smooth muscle found in the stomach and it is _______________

Back 40

oblique

Front 41

in the proximal portion of the esophagus the muscularis externa is what?

Back 41

skeletal muscle

Front 42

where is the muscularis externa skeletal muscle?

Back 42

proximal portion of the esophagus and outside of the anal canal wwall

Front 43

the serous membrane that will be on the outermost part of the GI tract portions in the abdominal cavity

Back 43

serosa

Front 44

what is another name for the serosa?

Back 44

visceral peritoneum

Front 45

the esophagus, ascending colon, descending colon, and most of the duodenum lack serosa and just have connective tissue so instead this is called?

Back 45

adventitia

Front 46

after food passes through the epithelial cells what 2 things can it pass into to travel around the body?

Back 46

blood vessels and lymphatic vessels

Front 47

where does the other 10% of digestion take place?

Back 47

stomach and large intestine

Front 48

what form of carbohydrates can be absorbed?

Back 48

monosaccharides

Front 49

what form of proteins can be absorbed?

Back 49

amino acids, dipeptides and tripeptides

Front 50

what form of triglycerides (large fats) can be absorbed?

Back 50

fatty acids and monoglycerides

Front 51

what form of nucleic acids (DNA and RNA) can be absorbed?

Back 51

nitrogenous bases, pentoses and phosphates

Front 52

this is formed by the cheeks, hard and soft palates superiorly and the tongue inferiorly; also known as the buccal cavity

Back 52

oral cavity

Front 53

fleshy folds that surround the opening of the mouth and contain the orbicularis oris muscle; also called the labia

Back 53

lips

Front 54

the oral cavity opens into the oropharynx through this opening

Back 54

fauces

Front 55

area between the lips and the teeth and between the cheeks and the teeth

Back 55

vestibule

Front 56

portion of the oral cavity behind the teeth

Back 56

oral cavity proper

Front 57

this action leads to the mechanical digestion of food

Back 57

masitcation

Front 58

these secrete saliva into the oral cavity

Back 58

major salivary glands

Front 59

the major salivary glands are stimulated to secrete by what?

Back 59

parasympathetic nervous system

Front 60

the largest of the 3 major salivary glands that lies between the skin and the masseter muscle just anterior to the ear

Back 60

parotid gland

Front 61

the parotid gland has a relatively long excretory duct called the parotid duct which opens into the mouth where?

Back 61

parotid papilla

Front 62

this is found on the cheek opposite the second molar

Back 62

parotid papilla

Front 63

this is the only major salivary glands located within the oral cavity

Back 63

sublingual gland

Front 64

this major salivary gland lies under the floor of the mouth along the medial surfaces of the mandible

Back 64

submandibular gland

Front 65

the submandibular gland also has a relatively long excretory duct called the submandibular duct which empties on either side of this

Back 65

lingual frenulum

Front 66

this ties the tongue to the mouth

Back 66

lingual frenulum

Front 67

this is the smallest major salivary gland and it is located beneath the tongue and superior to the submandibular glands

Back 67

sublingual gland

Front 68

these ducts open into the floor of the mouth to bring in saliva

Back 68

lesser sublingual ducts

Front 69

what is saliva composed of?

Back 69

99.5% water and 0.5% solutes

Front 70

how much saliva do we secrete daily?

Back 70

1000-1500 mL

Front 71

these receptors only respond to chemicals in aqueous solution

Back 71

chemoreceptors

Front 72

what are the buffer contents of the oral cavity?

Back 72

bicarbonate and phosphate ions

Front 73

saliva contains this enzyme that partially breaks down starch

Back 73

amylase

Front 74

in the oral cavity the food is reduced to a soft, small, easily swallowed mass known as what?

Back 74

bolus

Front 75

the bolus leaves through the _______________ and enters into the _________________

Back 75

fauces, pharynx

Front 76

this is a part of the digestive and respiratory systems

Back 76

pharynx

Front 77

this connects the nasal and oral cavities to the larynx and the esophagus

Back 77

pharynx

Front 78

the entrance from the pharynx to the larynx will be _______________

Back 78

anterior

Front 79

the entrance from the pharynx to the esophagus will be ________________

Back 79

posterior

Front 80

contraction of muscles in what parts of the pharynx help propel food into the esophagus?

Back 80

oropharynx and laryngopharynx

Front 81

the functions of this include a passageway for air and food, resonating sounds, and housing the tonsils

Back 81

pharynx

Front 82

these are composed of lymphatic tissue and participate in immunological reactions; found in the pharynx

Back 82

tonsils

Front 83

this part of the pharynx is for air passageway only and is found superior to the soft palate

Back 83

nasopharynx

Front 84

when swallowing, the soft palate and the uvula move superiorly to close this off?

Back 84

nasopharynx

Front 85

this part of the pharynx is found between the level of the soft palate to the epiglottis

Back 85

oropharynx

Front 86

this part of the pharynx is continuous with both the esophagus and the larynx inferiorly

Back 86

laryngopharynx

Front 87

after the pharynx, air goes into the ______________ and food goes into the _________________

Back 87

larynx, esophagus

Front 88

a 10 inch long collapsible muscular tube that connects the laryngopharynx to the stomach

Back 88

esophagus

Front 89

the esophagus is found ______________ to the trachea

Back 89

posterior

Front 90

what level does the esophagus go through the diaphragm at the esophageal hiatus?

Back 90

T10

Front 91

what level does the inferior vena cava go through the diaphragm?

Back 91

T8

Front 92

what level does the aorta go through the diaphragm?

Back 92

T12

Front 93

the muscularis externa of the superior 1/3 of the esophagus is ___________________ and the muscularis externa of the inferior 1/3 is ______________________

Back 93

skeletal muscle, smooth muscle

Front 94

the formal name for swallowing

Back 94

deglutition

Front 95

how long does it take for the bolus to go from the mouth to the stomach for solid/semisolid foods? for liquids

Back 95

4-8 seconds, 1 second

Front 96

no digestive enzymes are produced here, nor does any absorption take place here

Back 96

esophagus

Front 97

what are the functions of the esophagus?

Back 97

secrete mucous and transport food to the stomach

Front 98

J-shaped enlargement of the GI tract that connects the esophagus to the duodenum

Back 98

stomach

Front 99

the stomach receives the bolus from the esophagus but it passes _____________ on to the small intestine for further digestion and absoprtion

Back 99

chyme

Front 100

a pulpy, semi-fluid mixture of partially digested food and digestive secretions

Back 100

chyme

Front 101

how long does it usually take for the stomach to empty its food contents?

Back 101

4 hours

Front 102

where do carbohydrates begin their chemical digestion?

Back 102

in the mouth

Front 103

where do proteins and triglycerides begin their chemical digestion?

Back 103

in the stomach

Front 104

what nutrients can be absorbed in the stomach?

Back 104

water, some ions, some short chain fatty acids, drugs such as aspirin and alcohol

Front 105

the area that surrounds the superior opening of the stomach

Back 105

cardia

Front 106

this part of the stomach is superior and to the left of the cardia

Back 106

fundus

Front 107

in this area of the stomach gases can be collected and brought back up through belching

Back 107

fundus

Front 108

the large central portion of the stomach inferior to the fundus

Back 108

body

Front 109

where does the bolus spend most of its time in the stomach?

Back 109

body

Front 110

this part of the stomach connects the stomach to the duodenum

Back 110

pylorus

Front 111

this part of the pyloris is next to the body of the stomach; it is the proximal portion or the entrance to the pyloris

Back 111

pyloric atrium

Front 112

this is the distal part of the pyloris that leads into the duodenum

Back 112

pyloric canal

Front 113

when the stomach is empty the mucous lies in these longitudinal folds

Back 113

rugae

Front 114

do rugae alter the surface area available in the stomach?

Back 114

no

Front 115

the sphincter between the stomach and the duodenum

Back 115

pyloric sphincter

Front 116

this regulates the movement of chyme into the duodenum

Back 116

pyloric sphincter

Front 117

the concave medial border of the stomach is also known as what?

Back 117

lesser curvature

Front 118

folds of peritoneum between an organ and the body wall

Back 118

mesentery

Front 119

where does the visceral peritoneum become the lesser omentum

Back 119

lesser curvature of the stomach

Front 120

the convex lateral border of the stomach is also known as what?

Back 120

greater curvature

Front 121

this is where the visceral peritoneum becomes the greater omentum

Back 121

greater curvature of the stomach

Front 122

this is found in the wall of the stomach to provide more force for the mechanical digestion of food

Back 122

3rd inner oblique layer of muscles

Front 123

chyme has what pH due to the HCl in the stomach?

Back 123

very low

Front 124

ducts at the entrance of the small intestine bring secretions from what 2 accessory organs to increase the pH of chyme?

Back 124

liver and pancreas

Front 125

this elongated gland is found posterior to the greater curvature of the stomach and is approximately 5 inches long and 1 inch thick

Back 125

pancreas

Front 126

where does the head of the pancreas lie?

Back 126

in the C-shaped curve of the duodenum

Front 127

what position is the pancreas in because it doesn't need to move to do its job

Back 127

retroperitoneal

Front 128

what does the tail of the pancreas point towards?

Back 128

hilum of the spleen

Front 129

what percent of the pancreas functions as an exocrine gland? an endocrine gland?

Back 129

99%, 1%

Front 130

these synthesize and secrete enzymes into ducts

Back 130

exocrine glands

Front 131

pancreatic juice is secreted into small ducts which unite to form what?

Back 131

pancreatic duct (duct of Wirsung)

Front 132

this contains enzymes that digest starch, proteins, fats, nucleic acids, and sodium bicarbonate

Back 132

pancreatic juice

Front 133

the pancreatic duct and common bile duct join together to form what?

Back 133

hepatopancreatic ampulla

Front 134

this dumps into the duodenum at the major duodenal papilla

Back 134

hepatopancreatic ampulla

Front 135

what hormones does the pancreas secrete from the pancreatic islets?

Back 135

insulin and glucagon

Front 136

this is the second largest organ of the body and the largest internal organ of the body

Back 136

liver

Front 137

how much does the liver weigh?

Back 137

1500 grams (2.5% of an adult's body weight)

Front 138

the liver is located inferior to what?

Back 138

diaphragm

Front 139

what mesentery separates the right and left lobes of the liver

Back 139

falciform ligament

Front 140

this ligament is the remnant of the fetal umbilical vein and is located at the free border of the falciform ligament?

Back 140

round ligament of the liver (ligamentum teres hepatis)

Front 141

this mesentery helps attach the liver to the diaphragm

Back 141

coronary ligament

Front 142

when the coronary ligament gets into the diaphragm it is called what?

Back 142

parietal peritoneum

Front 143

a triangular space where the liver is attached to the diaphragm by fat tissue

Back 143

bare area of the liver

Front 144

this is where 25% of blood (oxygenated blood) enters the liver from the proper hepatic artery

Back 144

porta hepatis (hilum of the liver)

Front 145

deoxygenated blood enters the liver from what?

Back 145

portal hepatic vein

Front 146

oxygenated blood enters the liver from what?

Back 146

proper hepatic artery

Front 147

this comes out of the porta hepatis and brings bile out of the liver

Back 147

common hepatic duct

Front 148

along the superior edge of the liver are the hepatic veins which bring all of the blood out of the liver and dumb it into what?

Back 148

inferior vena cava

Front 149

liver cells

Back 149

hepatocytes

Front 150

how much bile do hepatocytes secrete daily?

Back 150

800-1000 mL

Front 151

this is partially an excretory product and partially a digestion secretion

Back 151

bile

Front 152

this is composed of water, bile salts, bilirubin, and elecrolytes

Back 152

bile

Front 153

these are emulsifying agents used for digestion and absorption of liquids; emulsifying cells help make large droplets of fat into smaller ones giving the enzymes more surface area to work on

Back 153

bile salts

Front 154

an end product of hemoglobin degradation

Back 154

bilirubin

Front 155

what detoxifies bilirubin?

Back 155

liver

Front 156

the major organ for taking aged red blood cells out of the bloodstream

Back 156

spleen

Front 157

this is a pigment that gives feces its color

Back 157

bilirubin

Front 158

the blood delivered by the hepatic portal vein is deoxygenated and contains newly absorbed nutrients, drugs, and possible microbes and toxin from what organs?

Back 158

gut and spleen

Front 159

what 3 lobes are actually considered one lobe because they get blood supply from similar vessels?

Back 159

left, caudate, and quadrate

Front 160

a pear shaped sac that is 3-4 inches and located in a depression on the posterior surface of the right lobe of the liver

Back 160

gallbladder

Front 161

the contraction of smooth muscle in the wall of the gallbladder causes it to eject its contents into what?

Back 161

cystic duct

Front 162

the function of this organ is to store and concentrate bile produced by the liver until it is needed in the small intestine

Back 162

gallbladder

Front 163

when do you need bile in the small intestine for emulsification?

Back 163

when you eat fatty food

Front 164

this is the only way into and out of the gallbladder

Back 164

cystic duct

Front 165

the presence of gallstones in the gallbladder or bile ducts

Back 165

cholelithiasis

Front 166

10-20% of people in developing countries have these but they are asymptomatic in about 50% of people who do

Back 166

gallstones

Front 167

what are gallstones composed of?

Back 167

cholesterol crystals

Front 168

what 3 things make you more susceptible to gallstones?

Back 168

female, fat and forty+

Front 169

these produce bile in the liver

Back 169

hepatocytes

Front 170

hepatocytes put bile into tiny ducts that lead into what two ducts?

Back 170

right and left hepatic

Front 171

the right and left hepatic ducts meet to form what?

Back 171

common hepatic duct

Front 172

the common hepatic duct leaves the liver from what side?

Back 172

posterior

Front 173

the common hepatic duct changes its name to this when it passes the cystic duct

Back 173

common bile duct

Front 174

the common bile duct meets up with the pancreatic duct to create this

Back 174

hepatopancreatic ampulla

Front 175

this opens up into the duodenum at the duodenal papilla

Back 175

hepatopancreatic ampulla

Front 176

this is in the major duodenal papilla and is made up of smooth muscle

Back 176

sphincter of Odie

Front 177

where does the chemical digestion of nucleic acids begin?

Back 177

small intestine

Front 178

where is all chemical digestion completed?

Back 178

small intestine

Front 179

the long length of the small intestine, plicae circulares, villi and microvilli all contribute to what?

Back 179

large surface area of the small intestine

Front 180

how long is the small intestine in a living person?

Back 180

10 feet

Front 181

the surface of the small intestine is arranged in these circular folds that are visible with the naked eye; they are permanent transverse folds and at their core is submucosa

Back 181

plicae circulares

Front 182

finger-like projections of the mucosa

Back 182

villi

Front 183

projections of the apical membrane of the intestinal absorptive cells

Back 183

microvilli

Front 184

what part of the large intestine does the small intestine open into?

Back 184

cecum

Front 185

what are the divisions of the small intestine from proximal to distal?

Back 185

duodenum, jejunum, ileum

Front 186

this connects the ileum and cecum

Back 186

ileocecal sphincter

Front 187

the terminal portion of the GI tract

Back 187

large intestine

Front 188

this is attached to the cecum

Back 188

vermiform appendix

Front 189

what are the 4 portions of the colon?

Back 189

ascending, transverse, descending, sigmoid

Front 190

the ascending colon is connected to the transverse colon here

Back 190

hepatic flexure (right colic flexure)

Front 191

the transverse colon is connected to the descending colon here?

Back 191

splenic flexure

Front 192

the opening of the anal canal to the exterior

Back 192

anus

Front 193

the cecum's and colon's outer longitudinal layer of the muscularis externa exhibits 3 thickened bands called what?

Back 193

teniae coli

Front 194

the cecum and colon exhibit these sacs or pouches

Back 194

haustra

Front 195

does the mucosa of the large intestine have plicae circulares or microvilli?

Back 195

no

Front 196

there are visible small fatty projections of the serosa called what on the outer surface of certain areas of the large intestine?

Back 196

omental appendices of epiploic appendages

Front 197

if not enough water is reabsorbed in the large intestine what will happen?

Back 197

diarrhea

Front 198

if too much water is reabsorbed in the small intestine what will happen?

Back 198

constipation

Front 199

these are found in the large intestine and can ferment remaining carbs, breakdown any remaining amino acids and synthesize vitamin B and K

Back 199

bacteria

Front 200

serous lining the abdominopelvic cavity

Back 200

parietal peritoneum

Front 201

serous lining of the viscera located in the abdominopelvic cavity

Back 201

visceral peritoneum

Front 202

this is found in the peritoneal cavity between the parietal and visceral peritoneums

Back 202

serous fluid

Front 203

organs that do not need to move as they function are not surrounded by the ______________

Back 203

peritoneum

Front 204

list the organs that are in the retroperitoneal position

Back 204

kidneys, adrenal glands, pancreas, ascending colon, descending colon, aorta and most of the duodenum

Front 205

these bind organs to one another and to the walls of the abdominal cavity

Back 205

mesentery

Front 206

these provide a highway for blood vessels, lymphatic vessels, and nerves that supply the abdominal organs

Back 206

mesenteries

Front 207

this attaches the small intestine to the posterior abdominal wall

Back 207

mesentery proper

Front 208

this attaches the colon to the posterior abdominal wall

Back 208

mesocolon

Front 209

this attaches the liver to the anterior abdominal wall and diaphragm

Back 209

falciform ligament

Front 210

this is the only abdominal organ attached to the anterior abdominal wall

Back 210

liver

Front 211

attaches the lesser curvature of the stomach and the liver

Back 211

lesser omentum

Front 212

this is the largest peritoneal fold that is considered the policeman of the abdomen as it has been found surrounding infections and trying to isolate them fro the rest of the abdominal cavity

Back 212

greater omentum