Digestive System Flashcards Preview

A&P II > Digestive System > Flashcards

Flashcards in Digestive System Deck (128):
1

What is another name for the GI tract?

alimentary canal

2

List the main organs in the digestive system

mouth, pharynx, esophagus, stomach, small intestine, and large intestine

3

List the accessory digestive organs

teeth, tongue, gallbladder, salivary glands, liver, and pancreas

4

In order, what are the main stages in the digestive process?

1. ingestion
2. Mechanical breakdown
3. Propulsion
4. Digestion
5. Absorption
6. Defecation

5

Which step in the digestive process are swallowing and peristalsis apart?

Propulsion

6

Define peristalsis

alting waves of contraction and relaxation

7

Which 3 components constituent mechanical breakdown?

chewing, churning, and segmentation

8

What is segmentation?

rhythmic local constrictions of small intestine

9

Passage of digested end products from GI tract lumen into blood or lymph

Absorption

10

Elimination of indigestible substances

Defecation

11

What controls GI tract motility and secretion?

Enteric nervous system

12

What provokes digestive activity?

mechanical and chemical stimuli

13

When stimulated, receptors in GI tract walls initiate reflexes that...?

1. activate/inhibit digestive glands
2. stimulate smooth muscle

14

T or F. Controls of digestive activity are both intrinsic and extrinsic

True

15

What are the 2 neural mechanisms?

1. Short reflexes- GI tract
2. Long reflexes- CNS center and ANS fibers

16

Describe hormonal mechanisms.

involve hormone-producing cells in stomach and small intestine

17

What covers the abdomen?

peritoneum

18

What type of peritoneum covers the organs?

visceral peritoneum

19

What comes between visceral and parietal peritoneum?

peritoneal cavity

20

What type of peritoneum lines the abdominopelvic cavity?

parietal peritoneum

21

What is the double layer of peritoneum that extends to digestive organs from body wall?

mesentery

22

What are the 4 layers of the alimentary canal?

muscosa, submucosa, muscularis externa, and serosa

23

Which layer of the alimentary canal consist of epithelium, lamina propria, and muscularis externa?

Mucosa

24

Dense connective tissue; contains blood vessels, lymphatics, and nerve fibers

Submucosa

25

visceral peritoneum

serosa

26

Inner circular layer; outer longitudinal layer

Muscularis externa

27

Bounded by lips, cheeks, palate, and tongue; lines by stratified squamous epithelium

Mouth (oral cavity)

28

Bone in the oral cavity

hard palate

29

Skeletal muscle

soft palate

30

What projects from free edges in the mouth?

uvula

31

Positions food during chewing, mixes food with saliva to form a bolus, initiates swallowing

tongue

32

What are the 3 salivary glands?

parotid gland, submandibular gland, and sublingual glands

33

What are the functions of the saliva?

cleanses mouth, dissolves food chemicals, moistens food, and begins chemical breakdown of starch

34

Between which 2 ages do teeth begin to erupt?

6-24 months

35

How many permanent teeth can one have?

32

36

What are the 4 classes of teeth? Amount upper L or R?

incisors (2), canines (1), premolars (2), and molars (3)

37

What are the 3 main parts of the teeth?

crown, neck, and root

38

Nasopharynx, Oropharynx, and laryngopharynx

Pharynx

39

Which organ is lined by the stratified squamous epithelium?

esophagus

40

Which digestive processes occur in the mouth?

ingestion, mechanical breakdown, propulsion, and digestion

41

Which digestive process occur in the pharynx and esophagus?

propulsion

42

How does mastication occur?

Cheeks and lips hold food between teeth, teeth cut and grind, and tongue from a bolus

43

How does deglutition occur?

tongue presses against hard palate and bolus is forced into oropharynx

44

Wha are the 2 phases in delglutition? voluntary?

Buccal phase- voluntary

Paryngeal-Esophageal Phase- Involuntary

45

What moves food through esophagus?

Peristalsis

46

What are the functions of the stomach?

temporary food storage (50mL/4L), begins chemical breakdown of proteins, and converts bolus to chyme

47

What controls food entry into the duodenum?

pyloric sphincter

48

What is the extra layer in the stomach?

oblique layer

49

In the stomach, where are gastric pits located?

mucosa

50

How are gastric juices produces?

gastric pits lead into gastric glands

51

What are the 4 major cells types in the gastric gland?

mucous neck cells, parietal cells, chief cells, and enteroendocrine cells

52

Required for absorption of vitamin B12

intrinsic factor

53

Secrete mucus

mucous neck cells

54

Secretes HCl and intrinsic factor, activate pepsin

Parietal cells

55

Secrete pepsinogen

chief cells

56

Secrete gastrin

enteroendocrine cells

57

Protects stomach mucosa, created by thick layer of bicarbonate-rich mucus

mucosal barrier

58

In mechanical breakdown, bolus is converted into..?

chyme

59

In Digestion, what is the purpose of HCl and pepsin?

HCl- denatures proteins

Pepsin- begins digestion of proteins

60

In propulsion, where is chyme delivered?

small intestines

61

In L, how much gastric juices is secreted per day?

3L

62

What regulates secretion?

long and short reflexes and hormones

63

What are the 3 phases of the gastric secretion?

cephalic, gastric, and intestinal

64

When does the cephalic phase occur?

Before food enters the stomach

65

What triggers the cephalic phase?

triggered by smell, taste, sight or thought

66

Which nerve stimulates the enteric neurons?

vagus causing secretion

67

When does the gastric phase occur?

once food reaches the stomach

68

How much gastric juice is the in the stomach?

2/3

69

What provoked the gastric phase?

distension of short and long reflexes, peptides and rising pH stimulate gastrin

70

When does the intestinal phase occur?

Once food enters the duodenum

71

How is the intestinal phase inhibited?

enterogastric reflex and release of intestinal hormones

72

What provokes the intestinal phase?

distension of duodenum, presence of fats, and acidic chyme

73

What is inhibited to promote gastric secretion?

Enteric neurons and vagus nerves

74

Which 2 hormones are secreted by intestinal hormones?

cholecystokinin and secretin

75

In gastric contractile activity what happen to chyme?

3 ml into dudoenum and 27mL forced back into stomach

76

Where does the small intestine begin or end?

begins at pyloric sphincter and ends at ileocecal valve

77

From proximal to distal what are the parts of the small intestine?

duodenum, jejunum, and ileum

78

Where are the bile duct and main pancreatic duct located?

Bile duct: from liver

Main pancreatic duct: pancreas unite in wall of duodenum

79

What controls entry of bile and pancreatic juice?

Hepatopancreatic sphincter

80

What are the 3 structural modifications in the small intestine?

circular folds, villi, microvilli

81

What is the function of the 3 structural modifications in the small intestine?

increase surface area for absorption

82

What forms the circular folds? Purpose

Formed by mucosa and submucosa.

Forces chyme ti slowly spiral through lumen

83

Fingerlike projections of mucosa and contain capillary beds and lacteals

Villi

84

Form brush border and brush border enzymes

microvilli

85

What do the pits of the villi lead?

intestinal crypts

86

Secretory cells

intestinal juice

87

lymphoid nodules in mucosa of ilium

peyer's patches

88

submucosa of duodenum, secrete alkaline in mucus

dudodenal glands

89

Produces bile

liver

90

stores and concentrates bile

gallbladder

91

Drains lover

common hepatic duct

92

drains gallbladder

cystic duct

93

What is formed by union of common hepatic and cystic ducts?

bile ducts

94

What are the 3 parts of the portal triad?

Hepatic artery, hepatic portal vein, and bile duct

95

Carries blood from digestive organs to liver for processing

hepatic portal vein

96

Oxygen-rich arterial blood in the liver

hepatic artery

97

Nutrient-rich venous blood in the liver

hepatic portal vein

98

Runs between hepatocyte platesq

liver sinusoids

99

What is the flow of blood in the liver?

hepatic artery and hepatic portal vein -> liver sinuoids-> central vein

100

Remove bacteria worn-out RBCs, and other debris from blood as flows past

Kupffer cells/ Stellate macrophages

101

Produce bile, process bloodbome nutrients, store fat-soluble vitamins and plays important role in detoxification

Hepatocyte

102

Secreted bile flows through what toward bile ducts?

bile canaliculi

103

Yellow-green alkaline solution

bile

104

cholesterol derivatives that function to emulsify fats

bile salts

105

bilirubin

chief bile pigment

106

Where in the pancreas do the exocrine functions occur?

acinar cells

107

How does the pancreatic juice enter the dudoenum

pancreatic duct

108

What are the 3 components pancreatic juice?

water, digestive enzymes, and bicarbonate ions

109

What causes the gallbladder to contract, stimulate secretion of enzyme-rich pancreatic juice and relaxes hepatopancreatic juice

CCK

110

stimulates secretion of bicarbonate-rich pancreatic rich

secretin

111

What digestive processes occur in the small intestine?

Mechanical breakdown and propulsion: segmentation and peristalsis

Digestion: enzymes from pancreas; brush border enzymes of microvilli

Absorption: Most water and virtually all nutrients absorbed

112

List what optimal digestive activity depends on:

1. bile from liver and gallbladder

2. Digestive enzymes from pancreas

3. Bicarbonate ions from the pancreas

4. Slow, measured delivery of chyme from stomach


113

Most common motion of small intestine, mixes chyme with bile, pancreatic juice, and intestinal juice, moves ileocecal valve

Segmentation

114

Begins late in intestinal phase

migrating motor complex

115

Which 2 mechanisms increase motility of ileum and cause ileocecal sphincter to relax?

Gastroileal reflex and gastrin released by stomach

116

Three bands of smooth muscle

teniae coli

117

Pocket-like sacs in wall of large intestine

Haustra

118

From small intestine to the anal canal where does the food go?

cecum, ascending colon, transverse colon, descending colon, sigmoid colon

119

List the subdivisions of the large intestine

cecum, appendix, colon, rectum, and ana canal

120

What are the 3 sphincters in the anus? Type of muscle?

Internal anal sphincter (smooth muscle) and external anal sphincter (skeletal muscle)

121

What type of epithelium is the large intestine? Anal Canal?

Large intestine: simple columnar epithelium

Anal canal: stratified squamous

122

What type of cells do large intestines contains that secrete mucus?

Goblet cells

123

What are the functions of the Bacterial flora in the large intestine?

colonize colo, ferment cellulose and other plant polysaccarides, synthesize B complex vitamins and vitamin K

124

What are the digestive process in the large intestine?

absorption- absorbs remaining water

Propulsion- propels feces toward rectum

Defacation- eliminates feces toward body

125

Long, slow-moving, powerful contractile waves, force contents toward rectum

Mass movements

126

Parasympathetic reflex that is initiated by stretching rectal wall.

Defecation reflex

127

What is the result of the defecation reflex

sigmoid colon and rectum contract and internal anal sphincter relaxes

128

What is the equation of the teeth?

(2I,1C,2PM,3M/21,1C,2PM,3M) x 2