The Digestive System

Front 1

Innermost tunic; consists of mucous epithelium, lamina propria, and muscularis mucosa

Back 1

Mucosa

Front 2

Tunic just outside the mucosa; a thick layer of loose connective tissue containing nerves, blood vessels, and small glands

Back 2

Submucosa

Front 3

Tunic composed of a circlar layer and a longitudinal layer of smooth muscle

Back 3

muscularis

Front 4

Outermost tunic; composed of epithelium or connective tissue

Back 4

Serosa or adventitia

Front 5

The lips are musclar structures formed mostly by the ________ muscle, and covered internally by mucosa and externally by stratisfied squamous epithelium.

Back 5

Orbicularis oris

Front 6

The ________ form the lateral walls of the oral cavity

Back 6

Cheeks

Front 7

Most of their thickness is contributed by the _______ muscle

Back 7

Buccinator

Front 8

The lips and cheeks are important in the process of ______ and speech

Back 8

Mastication

Front 9

The _________ is a large, musclar organ that occupies most of the oral cavity.

Back 9

Tongue

Front 10

The anterior portion of the tongue is attached to the floor of the mouth by a thin fold of tissue called the ________

Back 10

Frenulum

Front 11

The tongue is important in mastication, swallowing, speech, and is a major sensory organ for __________

Back 11

Taste

Front 12

Number of incisors in each quadrant of the adult mouth

Back 12

Two

Front 13

Number of canines in each quadrant of the adult mouth

Back 13

One

Front 14

Number of premolars in each quadrant of the adult mouth

Back 14

Two

Front 15

Number of molars in each quadrant of the adult mouth

Back 15

Three

Front 16

Deciduous teeth; also called milk teeth

Back 16

Primary teeth

Front 17

Teeth of the adult mouth

Back 17

Secondary teeth

Front 18

Sockets containing the teeth

Back 18

Alveoli

Front 19

Dense, fibrous connective tissue, and moist stratified squamous epithelium that vocer alveolar ridges

Back 19

Gingiva (gums)

Front 20

Connective tissue that holds the teeth in the alveoli

Back 20

Periodontal ligaments

Front 21

Cutting or chewing surface with one or more cusps (points )

Back 21

Crown

Front 22

Part of the tooth between the crown and the root

Back 22

Neck

Front 23

Center of the tooth; contains blood vessels, nerves, and onnective tissue

Back 23

Pulp cavity

Front 24

Connective tissue located in the pulp cavity

Back 24

Pulp

Front 25

Living, cellular, bonelike tissue surrounding the pulp cavity

Back 25

Dentin

Front 26

Extremely hard, acellular substance that protects the tooth against acids and abrasion

Back 26

Enamel

Front 27

Substance co ering dentin in the root; helps anchor teeth in the jaw

Back 27

Cementum

Front 28

Part of the tooth anchored in an alveolus by periodontal ligaments

Back 28

Root

Front 29

Anterior bony portion of the roof of the oral cavity

Back 29

Hard palate

Front 30

Posterior portion of the roof of the oral vaity, composed of skeletal muscle and connective tissue

Back 30

Soft palate

Front 31

Projection from the posterior edge of the soft palate; Prevents food from passing into the nasal cavity during swallowing

Back 31

Tonsils

Front 32

Collection of lymphoid tissue, located in the lateral posterior walls of the oral cavity

Back 32

Saliva

Front 33

Mixture of serous (watery) and mucous fluids that contains digestive enzymes

Back 33

Parotid glands

Front 34

Glands that produce more serous than mucous secretions; located along the inferior border of the mandible

Back 34

Submandibular gland

Front 35

Glands that produce mainly mucus, located below the mucous membrane in the floor of the oral cavity

Back 35

Sublingual glands

Front 36

Two portions of the pharynx that transmit food

Back 36

Oropharynx and laryngopharynx

Front 37

Form posterior walls of oropharynx and laryngopharynx

Back 37

Pharyngeal constrictors

Front 38

Cicular muscles that regulate the movement of food into and out of the esophagus

Back 38

Esophageal sphincters

Front 39

Opening between the esophagus and the stomach

Back 39

Cardiac opening

Front 40

Most superior portion of the stomach

Back 40

Fundus

Front 41

Formed when the body of the stomach turns to the right

Back 41

Greater and lesser curvatures

Front 42

Opening between stomach and small intestine

Back 42

Pyloric Opening

Front 43

Thick ring of smooth muscle that surrounds pyloric opening

Back 43

Pyloric sphincter

Front 44

Large folds of the submucosa and mucosa formed when the stomach is empty

Back 44

Rugae

Front 45

Tubelike openings in the mucosal surface of the stomach

Back 45

Gastric pits

Front 46

Glands in the stomach that open into the gastric pits

Back 46

Gastric glands

Front 47

Mucus-producing cells on the inner surface of the stomach and lining the gastric pits

Back 47

Surface mucous cells

Front 48

Mucus-producing cells in the gastric glands

Back 48

Mucous neck cells

Front 49

Gastric gland cells that produce hydrochloric acid and intrinsic factor

Back 49

Parietal cells

Front 50

Gastric gland cells that produce pepsinogen

Back 50

Chief cells

Front 51

Gastric gland cells that produce regulatory hormones

Back 51

Endocrine

Front 52

Two ducts that join together and empty into the duodenum

Back 52

1. Common bile duct
2. Pancreatic duct

Front 53

Folds in mucosal and submucosal layers that run perpendicular to the long axis of the digestive tract

Back 53

Circular folds

Front 54

Tiny fingerlike projections of the mucosa

Back 54

Villi

Front 55

Cytoplasmic extensions from cells on the surface of villi

Back 55

Microvilli

Front 56

Lymphatic capillaries found in villi

Back 56

Lacteals

Front 57

Junciton between the ileum and large intestine

Back 57

Ileocecal junction

Front 58

Ring of smooth muscle surounding the ileoceceal junction

Back 58

Ileocecal sphincter

Front 59

One-way valve at the junction between the ileum and small intestine

Back 59

Ileocecal valve

Front 60

Cells in duodenal mucosa with microcvilli; produce digestive enzymes and absorb food

Back 60

Absorptive cells

Front 61

Cells in duodenal mucosa that produce mucus

Back 61

Goblet cells

Front 62

Cells in duodenal mucosa that help protect intestinal epithelia brom bacteria

Back 62

Granular cells

Front 63

Cells in duodenal mucosa that produce regulatory hormones

Back 63

Endocrine cells

Front 64

Tubular glands at the base of villi; prodce epithelial cells

Back 64

Intestinal glands

Front 65

Mucous glands in the submucosa of the duodenum

Back 65

Duodenal glands

Front 66

Clusters of lymph nodules in the ileum

Back 66

Peyer's patches

Front 67

The ________ brings oygen rich blood into the liver

Back 67

Hepatic artery

Front 68

The __________ carries blood that is oxygen poor but rich in absorbed materials from the digestive tract to the liver

Back 68

Hepatic portal vein

Front 69

Blood exits the liver through __________

Back 69

Hepatic veins

Front 70

Right and left __________ transport bile from the liver and join to for the _____________

Back 70

Hepatic ducts
Common hepatic duct

Front 71

The common hepatic duct is joined by the _________ from the gallbladder to form the __________

Back 71

Cystic duct
common bile duct

Front 72

Joins the pancreatic duct to open into the duodenum at the _________

Back 72

Duodenal papilla

Front 73

The ______________ is a small sac on the inferior surface of the liver that stores bile

Back 73

gallbladder

Front 74

Subdivisions of the liver separated by connective tissue septa

Back 74

Lobules

Front 75

Coners of a liver lobule where three vessels are commonly located

Back 75

Portal triads

Front 76

Blood vessel in the center of each lobule

Back 76

Central vein

Front 77

Functional cells of the liver; produce bile

Back 77

Hepatocytes

Front 78

Platelike groups of hepatocytes between the central vein and margins of each lobule

Back 78

Hepatic cords

Front 79

Cleftlike opening between the cells of each hepatic cord; bile flows through this

Back 79

Bile canaliculus

Front 80

Blood channels that separate the hepatic cords.

Back 80

Hepatic sinusoids

Front 81

Exocrine portions of pancreas; produce digestive enxymes

Back 81

Acini

Front 82

Endocrine portion of the pancreas that produces insulin and glucagon

Back 82

Pancreatic islets

Front 83

Carries digestive enzymes; joins the common bile duct

Back 83

Pancreatic duct

Front 84

Blind sac that extends inferiorly past the ileocecal junction

Back 84

Cecum

Front 85

Small blind tube attached to the cecum

Back 85

Appendix

Front 86

Part of the colon closest to the cecum

Back 86

Ascending colon

Front 87

Extends from the right colic clexure to the left colic flexure

Back 87

Transverse colon

Front 88

Extends from the left colic flexure to the pelvis

Back 88

Descending colon

Front 89

S-shaped tube that ends at the rectum

Back 89

Sigmoid colon

Front 90

Straight tubular glands in the mucosal lining of the colon

Back 90

Crypts

Front 91

Three longitudinal smooth muscle bands that run the length of the colon

Back 91

Teniae coli

Front 92

Straight, muscular tube between sigmoid colon and anal canal

Back 92

Rectum

Front 93

The last 2 to 3 cm of the digestive tract

Back 93

Anal canal

Front 94

Thick involunatry smooth muscle layer at the superior end of the anal canal

Back 94

Internal anal sphincter

Front 95

Voluntary skeletal muscle at the inferior end of the anal canal

Back 95

External anal sphicter

Front 96

Serous membranes that cover the body wall of the abdominopelvic cavity

Back 96

Parietal peritoneum

Front 97

Connective tissue sheets; hold many abdominal organs in place

Back 97

Mesenteries

Front 98

Mesentery connecting the lesser curvature of the stomach to the liver and diaphragm

Back 98

Lesser omentum

Front 99

Pocket formed by the long, double fold of greater omentum

Back 99

Omental bursa

Front 100

Abdominal organs that lie against the abdominal wall, and have no mesenteries

Back 100

Retroperitoneal organs

Front 101

Starch-digesting enzyme in the serous portion of saliva

Back 101

Salivary amylase

Front 102

Enzyme in the serous portion of saliva that has a week antibacterial action

Back 102

Lysozyme

Front 103

Proteoglycan found in the muscous portion of saliva

Back 103

Mucin

Front 104

Phase of swallowing that involves forming a bolus of food and forcing it into the oropharynx

Back 104

Voluntary phase

Front 105

Reflex that involves closing the nasopharynx, forcing food through the pharynx, and covering the opening into the larynx

Back 105

Pharyngeal phase

Front 106

Phase of swallowing that uses peristaltic waves to move food from the pharynx to the stomach

Back 106

Esophageal phase

Front 107

Muscles that force food through the pharynx

Back 107

Pharyngeal constrictor muscles

Front 108

Part of the larynx that voers the opening into the larynx

Back 108

Epiglottis

Front 109

Wave of contraction of circular esophageal muscles preceded by a wave of relaxation

Back 109

Peristaltic waves

Front 110

Semifluid mixture of food and stomach secretions

Back 110

Chyme

Front 111

Substance that lubricates and protects the epithelial cells of the stomach wall

Back 111

Mucus

Front 112

Produces a low pH in the stomach and acts as an antimicrobial agent

Back 112

Hydrochloric acid

Front 113

Protein secreted by cheif cells

Back 113

Pepsinogen

Front 114

Enzyme produced from the conversion of pepsinogen by hydrochloric acid

Back 114

Pepsin

Front 115

Substance that binds with Vitamin B12 and makes it more readily absorbed in the ileum

Back 115

Intricsic Factor

Front 116

Hormone secreted by the stomach; helps regulate stomach secretions

Back 116

Gastrin

Front 117

Phase of stomach secetion that responds to taste, smell, thoughts of food, and sensations of chewing and swallowing

Back 117

Cephalic phase

Front 118

Phase of stomach secretion that is initiated by the presence of food in the stomach; greatest volume of gastric secretion

Back 118

Gastric phase

Front 119

Phase of stomach secretion that is controlled by the entrance of acidic chye into the duodenum

Back 119

Intestinal phase

Front 120

If the chyme has a pH of 2 or below, the hormone secretin is released, which _______ gastric secretion

Back 120

Decrease

Front 121

Fatty acids or lipids in the duodenum cause the secretion of cholecystokinin and gastric inhibitory peptide, which also cause a _________ in gastric secretion

Back 121

Decrease

Front 122

Relatively weak contractions of the stomach that cause ingested food to be mixed with stomach secretions

Back 122

Mixing waves

Front 123

Powerful contractions of the stomach that force chyme toward the pyloric sphincter

Back 123

Peristalitic waves

Front 124

Enzymes on the surface of intestinal wall epithelial cells that break down peptides into single amino acids

Back 124

Peptidases

Front 125

Enzymes on the surface of intestinal wall epithelial cells that break down disaccharides to monosaccharides

Back 125

Disaccharidases

Front 126

Secreted by duodenal glands and goblet cells

Back 126

Mucus

Front 127

Propagated for short distances, and function to mix intestinal contents

Back 127

Segmental contraction

Front 128

Proceed along the small intestine for variable distances; function to move chyme along the small intestine

Back 128

Peristaltic contraction

Front 129

Effect of secretin on bile secretion

Back 129

Stimulates

Front 130

Effect of cholecystokinin on contraction of the gallbladder

Back 130

Stimulates

Front 131

Effect of parasympathetic stimulation on bile secretion and release

Back 131

Stimulates

Front 132

Major proteolytic enzymes secreted by the pancreas

Back 132

Trypsin and Chymotrypsin

Front 133

Continues polysaccharide digestion that started in the oral cavity

Back 133

Pancreatic amylase

Front 134

Lipid-digesting enzyme

Back 134

Lipases

Front 135

Enzymes that break down DNA and RNA

Back 135

Nucleases

Front 136

Initiates the release of watery pancreatic solution that contains bicarbonate ions

Back 136

Secretin

Front 137

Stimulates relase of an enzyme-rich solution from pancreas

Back 137

Cholecystokinin

Front 138

Acidic chyme in duodenum stimulates release of this hormone

Back 138

Secretin

Front 139

Presence of fatty acids and aminoacids in duodenum stimulates release of this hormone

Back 139

Cholecystokin

Front 140

Absorbed from chyme in the production of feces

Back 140

Water and salts

Front 141

Secreted into chyme in the production of feces

Back 141

Mucus

Front 142

Responsible for vitamin K synthesis and 30% of the dry weight of feces

Back 142

Microorganism

Front 143

The process of elimination of feces

Back 143

Defication

Front 144

Strong peristaltic contractions that propel the contents of the colon considerable distances

Back 144

Mass movement

Front 145

Local and parasympathetic reflexes that result in relaxation of the internal anal sphincter and contraction of the rectum

Back 145

Defecatin reflex

Front 146

Breakdown of chemical bonds of organic molecules by digestive enzymes

Back 146

Digestion

Front 147

Begins in the stomach; most occurs in the duodenum and jejnum, although some occurs in the ileum

Back 147

Absorption

Front 148

Requires a carrier molecule; may require energy

Back 148

Transport

Front 149

Porduct of carbohydrate digestion

Back 149

Product of protein digestion

Front 150

Products of lipid digestion

Back 150

Fatty acids and Glycerol

Front 151

Enzyme that begins the digestion of carbohydrats in the mouth.

Back 151

Salivary amylase

Front 152

Enzyme that continues starch digestion in the duodenum

Back 152

Pancreatic Amylase

Front 153

Enzyme that is bound to the microvilli of intestinal epithelium

Back 153

Disaccharidase

Front 154

Other monosaccharies are converted into this molevule by the liver; transported by the circulatory system to cells that require energy

Back 154

Glucose

Front 155

Hormone that greatly increases the rate of glucose transport into most types of cells

Back 155

Insulin

Front 156

The direction of water movement when chyme is dilute

Back 156

Out of small intestine

Front 157

Fate of 99% of the water that is secreted into the stomach or small intestine

Back 157

Reabsorption

Front 158

Method of transport of sodium, potassium, and calcium, magnesium, and phosphate ions out of the small intestine

Back 158

Active Transport