Download Figure 22.2 Gastrointestinal tract activities.

Figure 22.2 Gastrointestinal tract activities.
Ingestion
Mechanical
breakdown
• Chewing (mouth)
• Churning (stomach)
• Segmentation
(small intestine)
Digestion
Food
Pharynx
Esophagus
Propulsion
• Swallowing
(oropharynx)
• Peristalsis
(esophagus,
stomach,
small intestine,
large intestine)
Stomach
Absorption
Lymph
vessel
Small
intestine
Large
intestine
Defecation
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Blood
vessel
Mainly H2O
Feces
Anus
Figure 22.3a Peristalsis and segmentation.
From
mouth
Peristalsis: Adjacent segments of alimentary tract
organs alternately contract and relax, moving food
along the tract distally.
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Figure 22.3b Peristalsis and segmentation.
Segmentation: Nonadjacent segments of
alimentary tract organs alternately contract and relax,
moving food forward then backward. Food mixing and
slow food propulsion occur.
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Figure 22.5a The peritoneum and the peritoneal cavity.
Abdominopelvic
cavity
Vertebra
Dorsal
mesentery
Parietal
peritoneum
Ventral
mesentery
Visceral
peritoneum
Peritoneal
cavity
Alimentary
canal organ
Liver
Two schematic cross sections of abdominal cavity illustrate
the peritoneums and mesenteries.
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Figure 18.24a Arteries of the abdomen.
Diaphragm
Abdominal
aorta
Inferior
phrenic
arteries
L. gastric artery
R. gastric
artery
Common
hepatic
artery
Hepatic
artery
proper
L
Splenic
artery
Gastroduodenal
artery
R
Celiac
trunk
R. gastroepiploic
artery
Middle
suprarenal
arteries
L. gastroepiploic artery
Intestinal arteries
Middle colic
artery
Superior
mesenteric
artery
R. colic
artery
Renal
arteries
Gonadal
arteries
Ileocolic artery
Sigmoidal
arteries
Inferior
mesenteric
artery
L. colic
artery
Lumbar
arteries
Superior rectal
artery
Median sacral artery
Common iliac arteries
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Schematic flowchart.
Figure 18.29a Veins of the abdomen.
Inferior vena cava
Cystic vein
Hepatic
portal
system
Inferior phrenic veins
Hepatic veins
Hepatic portal vein
Superior mesenteric vein
Splenic vein
Suprarenal veins
Renal veins
Inferior
mesenteric
vein
Gonadal veins
Lumbar veins
R. ascending
lumbar vein
L. ascending
lumbar vein
Common iliac veins
External iliac vein
Internal iliac veins
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Schematic flowchart.
Figure 22.6 Basic structure of the alimentary canal.
Intrinsic nerve plexuses
• Myenteric nerve plexus
• Submucosal nerve plexus
Glands in
submucosa
Mucosa
• Epithelium
• Lamina propria
• Muscularis
mucosae
Submucosa
Muscularis externa
• Longitudinal muscle
• Circular muscle
Mesentery
Nerve
Gland in mucosa
Artery
Vein
Duct of gland outside
Lymphatic vessel
alimentary canal
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Serosa
• Epithelium
(mesothelium)
• Connective tissue
Lumen
Mucosa-associated
lymphoid tissue
Figure 19.2a The lymphatic system.
Regional
lymph
nodes:
Internal
jugular vein
Entrance of
right lymphatic
duct into vein
Cervical
nodes
Entrance of
thoracic duct
into vein
Thoracic
duct
Axillary
nodes
Cisterna
chyli
Aorta
Collecting
lymphatic
vessels
Drained by the right lymphatic duct
Drained by the thoracic duct
Inguinal
nodes
General distribution of collecting lymphatic
vessels
and regional lymph nodes.
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Inc.
Figure 22.12a Microscopic structure of the esophagus.
Mucosa
(stratified
squamous
epithelium)
Submucosa
(areolar
connective
tissue)
Lumen
Muscularis
externa
• Circular layer
• Longitudinal
layer
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Adventitia
(fibrous
connective
tissue)
Figure 22.7b Anatomy of the oral cavity (mouth).
Upper lip
Gingivae
(gums)
Palatine
raphe
Hard
palate
Soft
palate
Uvula
Palatine
tonsil
Superior
labial
frenulum
Palatoglossal
arch
Palatopharyngeal
arch
Posterior wall
of oropharynx
Tongue
Sublingual
fold with
openings of
sublingual
ducts
Lingual frenulum
Opening of
Submandibular
duct
Gingivae (gums)
Oral vestibule
Lower lip
Anterior view
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Inferior labial
frenulum
Figure 22.9 The salivary glands.
Tongue
Teeth
Ducts of
sublingual
gland
Frenulum
of tongue
Sublingual
gland
Parotid
gland
Parotid duct
Masseter muscle
Body of mandible
(cut)
Posterior belly of
digastric muscle
Mylohyoid
muscle (cut)
Submandibular
duct
Anterior belly of
digastric muscle
Submandibular
gland
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Mucous cells
Serous cells
forming demilunes
Figure 22.11 Longitudinal section of a canine tooth within its bony socket (alveolus).
Enamel
Dentin
Crown
Neck
Dentinal
tubules
Pulp cavity
(contains
blood vessels
and nerves)
Gingival
sulcus
Gingiva
(gum)
Cement
Root
Root canal
Periodontal
ligament
Apical
foramen
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Bone
Figure 22.7a Anatomy of the oral cavity (mouth).
Soft
palate
Palatoglossal
arch
Uvula
Hard
palate
Oral cavity
Palatine
tonsil
Tongue
Oropharynx
Lingual tonsil
Epiglottis
Hyoid bone
Laryngopharynx
Esophagus
Trachea
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Sagittal section of the oral cavity and pharynx
Figure 22.13 Deglutition (swallowing).
Bolus of food
Tongue
Uvula
Pharynx
Bolus
Epiglottis
Epiglottis
Glottis
Trachea
Esophagus
1 During the buccal phase, the upper
esophageal sphincter is contracted.
The tongue presses against the hard
palate, forcing the food bolus into the
oropharynx.
2 The pharyngeal-esophageal phase
begins as the uvula and larynx rise to prevent
food from entering respiratory passageways.
The tongue blocks off the mouth. The upper
esophageal sphincter relaxes, allowing food
to enter the esophagus.
4 Peristalsis moves
food through the
esophagus to the
stomach.
Relaxed muscles
Circular muscles
contract
Upper
esophageal
sphincter
Bolus
3 The constrictor muscles of the
pharynx contract, forcing food into
the esophagus inferiorly. The upper
esophageal sphincter contracts
(closes) after food enters.
Relaxed
muscles
5 The gastroesophageal
sphincter surrounding the
cardial oriface opens, and
food enters the stomach.
Bolus of food
Longitudinal muscles
contract
Circular muscles contract
Gastroesophageal
sphincter closed
Gastroesophageal
sphincter opens
Stomach
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Figure 22.13 Deglutition (swallowing). (4 of 5)
4 Peristalsis moves
Relaxed muscles
food through the
esophagus to the
stomach.
Circular muscles
contract
Bolus of food
Longitudinal muscles
contract
Gastroesophageal
sphincter closed
Stomach
© 2014 Pearson Education, Inc.
Figure 22.13 Deglutition (swallowing). (5 of 5)
Relaxed
muscles
5 The gastroesophageal
sphincter surrounding the
cardial oriface opens, and
food enters the stomach.
Circular muscles contract
Gastroesophageal
sphincter opens
© 2014 Pearson Education, Inc.
Figure 22.14a Anatomy of the stomach.
Cardia
Fundus
Esophagus
Muscularis
externa
• Longitudinal layer
• Circular layer
• Oblique layer
Serosa
Body
Lumen
Lesser
curvature
Rugae of
mucosa
Greater
curvature
Duodenum
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Pyloric sphincter
(valve) at pylorus
Pyloric
canal
Pyloric
antrum
Figure 22.15b Microscopic anatomy of the stomach.
Gastric pits
Surface epithelium
(mucous cells)
Gastric
pit
Mucous neck cells
Parietal cell
Gastric
gland
Chief cell
Enteroendocrine cell
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Enlarged view of gastric pits and
gastric glands
Figure 22.22a Structural modifications of the small intestine that increase its surface area for digestion and absorption.
Vein carrying
blood to
hepatic portal
vessel
Muscle
layers
Circular
folds
Villi
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Lumen
Figure 22.22b Structural modifications of the small intestine that increase its surface area for digestion and absorption.
Microvilli
(brush border)
Absorptive
cells
Lacteal
Villus
Goblet
cell
Blood
capillaries
Mucosaassociated
lymphoid
tissue
Intestinal
crypt
Muscularis
mucosae
Duodenal
gland
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Enteroendocrine
cells
Venule
Lymphatic vessel
Submucosa
Figure 22.29a Gross anatomy of the large intestine.
Left colic
(splenic) flexure
Transverse
mesocolon
Right colic
(hepatic) flexure
Transverse colon
Epiploic
appendages
Superior
mesenteric artery
Haustrum
Descending colon
Ascending colon
IIeum
Cut edge of
mesentery
IIeocecal valve
Tenia coli
Sigmoid colon
Cecum
Appendix
Rectum
Anal canal
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External anal sphincter
Figure 22.30c Mesenteries of the abdominal digestive organs.
Greater omentum
Transverse colon
Transverse
mesocolon
Descending colon
Jejunum
Mesentery
Sigmoid
mesocolon
Sigmoid colon
Ileum
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