DIGESTIVE SYSTEM Flashcards
(103 cards)
1
Q
Consists of a long muscular tube beginning
from the lips to the anus
A
Alimentary tract
2
Q
– Salivary glands
– Liver
– Biliary tract
– Pancreas
A
Accessory organs
3
Q
4 Layers
A
Mucosa
Submucosa
Tunica muscularis
Serosa
4
Q
Lining epithelium
A
Mucosa
5
Q
highly vascular loose CT;
contains fibroblasts, reticular and elastic
fibers, macrophages, aggregates of lymphoid
tissue
A
Lamina propria
6
Q
thin layer of smooth
muscle which separates mucosa from
submucosa
A
Muscularis mucosa
7
Q
Layer of dense CT containing many
blood vessels and a plexus of
sympathetic nerves called Meissner’s
plexus which controls the intrinsic
motility of the walls of the GIT
A
Submucosa
8
Q
Layer of dense CT containing many
blood vessels and a plexus of
sympathetic nerves
A
Meissner’s
plexus
9
Q
Composed of smooth muscle cells
spirally oriented into 2 sublayers
A
Tunica muscularis
10
Q
circular
A
Internal
11
Q
longitudinal
A
External
12
Q
Between the layers is a second
sympathetic nerve plexus called
A
Auerbach’s plexus
13
Q
coordinates the peristaltic contractions
A
Auerbach’s plexus
14
Q
Outermost layer consisting of mesothelium which lines the abdominal cavity and covers the organs within it
A
Serosa
15
Q
Main functions of the digestive tract’s lining epithelium:
A
Provide a selective permeable barrier
Facilitate the transport and digestion of food
Promote the absorption of the products of digestion
Produce hormones
Produce mucus for lubrication and protection
16
Q
Serves as the entrance to the digestive tract
A
Oral Cavity
17
Q
Has a lumen and surrounding coats or layers
A
Oral Cavity
18
Q
Mucous membrane
Stratified squamous nonkeratinizing epithelium
Lamina propria, muscularis mucosa, submucosa layers
Palate
Pharynx
A
Oral Cavity
19
Q
Orbicularis oris skeletal muscle and dense connective tissue
A
Lips
20
Q
lined by stratified squamous nonkeratinizing
epithelium
A
Oral side
21
Q
outer portion covered by typical thin skin; has hair
follicles, sweat glands, sebaceous glands
A
Skin side
22
Q
red free edge of the lips; hairless very thin skin, transparent permitting the blood in the capillaries of the dermis to impart to it a red color
A
Vermilion border
23
Q
Freely movable organ attached to the floor of the mouth and the hyoid bone
A
Tongue
24
Q
Consists of interlacing bundles of skeletal muscles
A
Tongue
25
Lining epithelium of tunica mucosa is stratified squamous epithelium
Dorsal surface is covered by a relatively thick epithelium
26
Acinar glands
Secretes about 1.5-2 L of fluid /day
Pancreatic juice rich in bicarbonate ions and digestive enzymes (amylase, lipase, trypsinogen, proteases, nucleases, proelastases)
Duct of Wirsung
Exocrine
27
Transversely-oriented retroperitoneal organ extending from the “C” loop of the duodenum to the spleen
EXOCRINE PANCREAS
28
20 cm in length; 85-90 grams
Head, body and tail
EXOCRINE PANCREAS
29
Thin muscularis and absent submucosa
Cystic duct joins the common hepatic duct to form the common bile duct which empties into the 2nd portion of duodenum; opening is ampulla of Vater
Gallbladder
30
Hollow pear-shaped sacular organ lodged in the inferior surface of the right lobe of the liver
Gallbladder
31
10x4 cm; capacity of 40-70 ml bile
Fundus, body and neck
Gallbladder
32
Processing of amino acids, carbohydrates, lipids, and vitamins
Removal of microorganisms and toxins
Synthesis of plasma proteins
Detoxification and excretion into bile of endogenous waste products and pollutants
Functions of the Liver
33
Polygonal or hexagonal
Mass of liver parenchyma surrounded by the central vein
Portal triads in every corner of the hexagon
Liver: Classical Lobule
34
Largest gland in the body
1.5 kg in the adult
LIVER
35
Divided into right and left lobes
On its underside, blood vessels and bile ducts pass through its hilum or porta hepatis
LIVER
36
Dual blood supply
Receiving well oxygenated blood from the systemic circulation via the hepatic artery (25%)
Larger volume (75%) of poorly oxygenated blood coming from the intestinal tract via the portal vein
LIVER
37
Bile
Exocrine gland
38
Proteins and glucose
Endocrine gland
39
small triangular areas which are thickenings of CT which enclose
Portal triads
40
Glisson’s capsule
Stroma
41
Liver cells or hepatocytes which are arranged on hepatic cords or plates oriented radially from a central vein (branch of hepatic vein)
Parenchyma
42
discontinuous basal lamina that separates endothelial cells from underlying hepatocytes
Perisinusoidal space (space of Disse),
43
are found in between cords or plates: simple squamous epithelium, Kupffer cells, fat storing cells (Ito cells)
Hepatic sinusoids
44
minute canals that run between liver cells throughout the liver parenchyma
Bile canaliculi
45
Bile drains from canaliculi into terminal ductules, to interlobular bile ducts (portal triad), then into the right and left hepatic bile duct, common hepatic duct joins cystic duct to form common bile duct
46
Largest; subcutaneous; on either side of face below ears
Parotid
47
Stensen’s
Parotid
48
Exclusively serous
Parotid
49
Parotid
50
On either side, between the mandible & muscles that form the floor of mouth
Submandibular
51
Predominantly serous
Submandibular
52
Wharton’s
Submandibular
53
Floor of mouth
Submandibular
54
Deep in the floor of mouth near frenulum
Sublingual
55
Predominantly mucous
Sublingual
56
Often joins submandibular
Sublingual
57
Floor of mouth
Sublingual
58
Located deep in the floor of the mouth near the frenulum
Predominantly mucous secretions
Duct often joins the submandibular gland
Open at floor of the mouth
Sublingual Glands
59
Located on either side between the mandible and muscles that form the floor of the mouth
Predominantly serous secretions
Wharton’s duct opens at the floor of the mouth
Submandibular Glands
60
Parotid Glands
Largest among the salivary glands
Subcutaneous location on either side of face below the ears
Predominantly serous secretions
Stensen’s duct opens on the inside of cheek opposite the 2nd upper molar
61
SALIVARY GLANDS
Parotid Gland
Submandibular Gland
Sublingual Gland
62
6-7 cm long structure attached to the cecum
Has same 4 layers
Extremely rich lymphoid tissue in the mucosa and submucosa
APPENDIX
63
Tunica muscularis: outer longitudinal layer are grouped into 3 evenly spaced longitudinal bands called taenia coli
LARGE INTESTINE
(Colon)
64
Haustra
Serosa: conspicuous accumulations of adipose tissue beneath the mesothelium that forms pendulous protuberances called appendices epiploicae
65
Mucosa is simple columnar epitheliumwith few short irregular microvilli
– Absorptive cells or colonocytes
No villi
Numerous goblet cells
Crypts of Leiberkuhn are larger and longer
LARGE INTESTINE
(Colon)
66
Mucosa is simple columnar epitheliumwith few short irregular microvilli
– Absorptive cells or colonocytes
No villi
Numerous goblet cells
Crypts of Leiberkuhn are larger and longer
LARGE INTESTINE
(Colon)
67
1.5 meters long
Segments
Cecum
Ascending colon
Transverse colon
Descending colon
Sigmoid colon
Rectum
Anus
LARGE INTESTINE
(Colon)
68
Filliform
Fungiform
Circumvallate
Foliate – rudimentary in man
4 types of lingual papillae
69
Anterior to the sulcus terminalis, the dorsum is rough covered by numerous excrescences called lingual papillae
Anterior 2/3
70
Most abundant
Elongated conical in form and slightly curved
The heavily keratinized cells at the tips of the papillae are continuously exfoliated
Epithelium lacks taste buds
Filiform papillae
71
Have narrow base and slightly flattened, mushroom-shaped
Scattered taste buds on upper surfaces
Lightly keratinized
Less numerous and scattered singly among the filiform papilla
Fungiform papillae
72
Poorly developed
Parallel ridges and furrows on the sides of the tongue
With taste buds
Foliate papillae
73
Number only 6-14 and are confined to the posterior part where they are aligned just in front of the sulcus terminalis
Circumvallate papillae
74
Epithelium on the free surface is smooth and that on the sides of the papilla contains numerous taste buds
total number of taste buds in a single papilla is average of 250
Circumvallate papillae
75
3,000 on the human tongue
Pale ovoid bodies within the lingual and oral epithelium
contain 50-75 cells
Taste Buds
76
Have long microvilli or apical processes that extends to the taste pore to the free surface
Tips of these apical processes are receptors for the sense of taste
Gustatory (taste) cells
77
Basal cells which divide and give rise to
above cells
Stem cells
78
Slender and immature cells
Supporting cells
79
5 Basic Taste Sensations
Sour
Sweet
Salty
Bitter
Umami
80
Pharyngeal part or root of tongue
Surface shows many bulges due to lingual tonsils and lymphoid nodules
Lacks papillae
Posterior 1/3
81
Diciduous or milk teeth: 20
Permanent or succidaneous teeth: 32
2 sets
82
Dentin - odontoblasts
Enamel - ameloblasts
Cementum - cementoblasts
Hard
83
Pulp
Periodontal membrane
Gingiva
Soft
84
Nasopharynx
Oropharynx
Laryngopharynx
3 portions of pharynx
85
25 cm long
Upper, middle, lower third 3rd
Located in the thorax, passing through the diaphragm to join the stomach, its terminal 2-4 cm is in the abdominal cavity
ESOPHAGUS
86
Stratified squamous, non-keratinizing
Submucosa has esophageal glands
Tunica muscularis
ESOPHAGUS
87
skeletal muscle
Proximal 3rd
88
combination of skeletal and
smooth
Middle 3rd
89
smooth muscle
Distal 3rd
90
The most dilated portion of the GIT
Mainly for digestion and storage of food
STOMACH
91
cardia
fundus
corpus
pylorus
4 regions are distinguished STOMACH
92
Mucosa: simple columnar epithelium which invaginates into lamina propria forming gastric pits (foveolae)
STOMACH
93
Mucosa and submucosa form longitudinal folds called
rugae
94
Each gland has isthmus, neck, base
Simple branched tubular
95
Mucous glands: mucous
Stem cells
Chief cells: proteolytic enzyme pepsin
Parietal cells: HCl acid
Neuroendocrine cells
5 cell types of stomach gastric galnds
96
4-7 meters in length
SMALL INTESTINE
97
Duodenum: C-shaped which surrounds the head of pancreas
Jejunum: suspended from the dorsal wall by mesentery and is freely movable
Ileum: attached to cecum
SMALL INTESTINE
98
C-shaped which surrounds the head of pancreas
Duodenum
99
suspended from the dorsal wall by mesentery and is freely movable
Jejunum
100
attached to cecum
Ileum
101
Goblet mucous glands
Paneth cells
Enteroendocrine cells
M (microfold) cells
Brunner (duodenal) glands
SMALL INTESTINE
Intestinal Mucosa
102
Mucosa is simple columnar epithelium
Absorptive cells or enterocytes
Surface have brush border (striated border) which on E/M are seen as closely packed microvilli numbering up to 3000 per cell resulting in a 30-fold increase in its absorptive function
SMALL INTESTINE
Intestinal Mucosa
103
Consist of structures that increase its absorptive function
Plicae circularis or valves of Kerkring: crescentic folds; permanent folds
Intestinal villi: 0.5-1.5 mm long finger-like projection of the mucosa
Crypts of Liberkuhn: invaginations of the mucosa (tubular glands) between the bases of the villi
SMALL INTESTINE
Intestinal Mucosa
