A&P II Digestive Chapter 24
deglutition involves 3 major phases called
1. buccal phase 2. pharyngeal phase 3. esophageal phase
2 major body systems that control the digestion in any organ of the GI tract
1. endocrine system 2. nervous system
the mucosa has 3 tissue layers
1. epithelium 2. lamina propria 3. muscularis mucosa
5 types of peritoneal folds of tissues
1. greater omentum 2. lesser omentum 3. falciform ligament 4. mesocolon 5. mesentery proper
3 types of teeth
1. incisor 2. molar 3. canine
name 2 types of tissues that make up a serous membrane
1. mesothelium 2. areolar tissue
name the structures of the alimentary canal (actual GI tract) from the mouth to the anus
1. mouth, 2. pharynx 3. esophagus 4. stomach 5. small intestine 6. large intestine 7. anus
what are the 4 histological layers of the esophagus
1. mucosa 2. submucosa 3. muscularis externa 4. adventitia
the walls of hollow organs contain 4 histological layers
1. mucosa 2. submucosa 3. muscularis externa 4. serosa or adventitia
4 key components of saliva
1. mucus and h20 2. lysozyme 3. ions 4. amylase - chemical digestion of carbs
3 parts of the pharynx
1. oropharynx 2. nasopharynx 3. laryngopharynx
the autonomic nervous system includes 3 types nervous systems
1. parasympathetic 2. sympathetic 3. enteric nervous system
2 layers of peritoneum
1. parietal peritoneum 2. visceral peritoneum
3 types of salivary glands in the accessory digestive organs
1. parotid glands 2. submandibular glands 3. sublingual glands
name 5 key characteristics of enzymes
1. they are proteins= made up of amino acids 2. work by "lock and key" mechanism. only catalyze one type of reaction 3. can be used over and over. they aren't used up cause they aren't changed during reaction. 4. speed up reaction so they can occur at a rate fast enough to maintain life processes. 5. they have a specific pH and temperature at which they work best
the esophagus is how long
12 inches long
how many deciduous teeth are found in children
20
what is amylase's optimal pH
5
what is the difference between the actual gastrointestinal tract and the accessory digestive organs?
Actual GI tract= food passes through Accessory digestive organs= food doesn't pass through
what type of plexus' does the enteric nervous system include
Myenteric (Auerbach) plexus and submucosal plexus
which cranial nerve innervate the salivary glands
VII facial, IX glossopharyngeal, X vagus
which cranial nerve innervates tongue muscles
XII hypoglossal
what type of tissue is found the lamina propria
areolar tissue with blood vessels
what is the purpose of the tongue
assist in chewing and help prepare bolus for swallowing; also touch, temp. and taste receptors
where is parietal peritoneum located
attached to wall of abdominal cavity
what is labial frenulum
attaches to the center of the upper lip and between upper 2 front teeth
how is salivation controlled
autonomic nervous system
what are deciduous teeth
baby teeth
where is greater omentum located
between the body wall and the anterior surface of the small intestine
where is the falciform ligament located
between the liver and the anterior abdominal wall
where is the lesser omentum located
between the stomach and the liver
what happens in esophageal phase
bolus in esophagus
what happens in pharyngeal phase
bolus passes pharynx
does deglutition involve smooth, skeletal muscle or both? explain
both **
what is digestion
breaking down food; mechanical and chemical
what is hydrolysis
breaking of a bond in a molecule using water
what part of deglutition is voluntary
buccal phase
what is the function of the myenteric (Auerbach) plexus
carries impulses for the smooth muscle of the muscularis externa
what is mastication
chewing and breaking down food through the mouth
what is the function of incisor
clipping or cutting
what is a bolus
compact mass of food to be digested
what is meant by intraperitoneal organs
completely surrounded by peritoneum
what is the purpose of the lingual frenulum
connect the body of the tongue to mucosa covering the floor of oral cavity
what type of tissue is found in submucosa
connective tissue
what happens in buccal phase
creates bolus
what is the function of molar
crushing and grinding
the sympathetic nervous system _____ motility and secretion in the GI tract
decreases
what is meant by retroperitoneal organs
don't have visceral peritoneal on all sides
examples of retroperitoneal organs
duodenum and pancreas
what is chemical digestion
enzymes by hydrolysis
how does the body ensure that food enters the esophagus and not the larynx
epiglottis
what does the peritoneal cavity contain
fluid to reduce friction between organs
parietal and visceral peritoneum are connected by
folds of tissues
the mucosa is the layer that comes in contact with
food (luminal side)
the nerve plexus of the submucosa regulates
glands and muscularis mucosa
which nerve is a major player in degluition
glossopharyngeal nerve
which cranial nerves are involved in deglutition
glossopharyngeal, vagus, and hypoglossal
what is gingiva
gums
what is the function of the tonsils
have immune tissue to fight off infection
name 2 functions of papillae located on the tongue
help move objects around the mouth taste
what is the function of the enteric nervous system
helps control motility and secretion.
which important blood vessels are found in the lesser omentum
hepatic portal vein, common hepatic artery, common bile duct, and some lymph nodes
what happens in the endocrine system
hormones secreted into the blood to act on a specific target organ
by what process does amylase break down carbohydrates
hydrolysis
chemical digestion occurs by a process called
hydrolysis
what is the function of the enzyme, amylase**
hydrolysis of carbs to monosaccharides
when do organs have a adventitia
if they are located outside of the peritoneal cavity
where are the cells in the salivary glands arranged at
in an acinar or alveolar (spherical) structure
where is the parotid gland located
in the cheek
where is the submandibular gland located
in the jaw
where are the goblet cells located in the mucosa
in the secretory cells of stomach mucosa
does parasympathetic stimulation increase or decrease secretion of saliva
increase
the parasympathetic nervous system ____ motility and secretion in the GI tract
increase
compared to the inner circular layer of muscle, where is the outer longitudinal layer
inner circular = top outer longitudinal = bottom
2 layers of muscle of the muscularis externa
inner circular layer of muscle outer longitudinal layer of muscle
where does most absorption occur in the GI tract
jejunum
what is a serous membrane
lining of cavities, lubrication
what is labia
lips
where is visceral peritoneum located
located directly on organs in the abdominal cavity
name the place where the esophagus perforates the diaphragm
lower esophageal sphincter
name a skeletal muscle that closes the mouth
massseter
which 2 bones make up the hard palate
maxilla and palatine
which 2 bones have sockets for teeth
maxillae and mandible*
where is deglutition controlled
medulla oblongata= swallowing center
what are some functions of saliva
moistening food and helping to create a food bolus so it can swallow easily
what 3 parts of the GI tract is epithelium tissue layer found in
mouth, pharynx, esophagus
where does food go once it is absorbed
moves from the lumen into the bloodstream (to nourish body)
what type of gland is the sublingual gland
mucus
sandwiched between the circular and longitudinal layers is the
myenteric (Auerbach) plexus
what happens in the nervous system
nervous control of the digestive system involves intrinsic nerves (enteric nervous system) and extrinsic nerves (parasympathetic and sympathetic nervous system)
what is the significance of the lower esophageal sphincters
opens to allow food into stomach closes to food going back up
what is significance of the upper esophageal sphincter
opens when you swallow
which parts of the pharynx are passageways for both food and air
oropharynx and laryngopharynx
which of the salivary glands has the longest duct and why is that significant
parotid, because it makes very watery saliva
what is the role of the pharynx in deglutition
passes food and fluids from the mouth toward the esophagus during deglutition
the space between the visceral and parietal peritoneum layers is called
peritoneal cavity
what part of deglutition is involuntary
pharyngeal phase
what is mechanical digestion
physical grinding of food by churning and chewing
is the esophagus anterior or posterior to the larynx and trachea
posterior
is water a reactant or a product in a hydrolysis reaction
reactant
where is amylase made
salivary glands
give examples of accessory digestive organs
salivary glands, pancreas, liver, gall bladder
what does the enteric nervous system also include
sensory neurons that can detect the presence of certain foods (chemoreceptors) or stretch of an organ
what type of gland is the parotid
serous
what type of gland is the submandibular gland
serous and mucus
what is peritoneum
serous membrane that lines the abdominal cavity
what is the function of the outer longitudinal layer of muscle
shortens
what type of tissue does the serous layer contain
simple squamous with areolar tissue under the adventitia
does the pharynx have skeletal or smooth muscle
skeletal muscle
together the function of inner circular and outer longitudinal layer of muscle
smooth muscle that allows for peristalsis
what is the function of the inner circular layer of muscle
squeezes
examples of intraperitoneal organs
stomach, spleen, liver, transverse colon, small intestine, gall bladder
what is the tissue found in gingiva
stratified squamous
what type of tissue is found in the epithelium
stratified squamous and simple columnar????
what type of tissue does all of the parts of pharynx contain
stratified squamous epithelium
what is unique about the mucosa that helps the esophagus perform its function
stratified squamous for protection
what type of tissue does the mouth contain
stratified squamous for protection
what type of nerve plexus are found in the submucosa
submucosal or Meissner plexus
what is the significance of the soft palate
supports the uvula
what is deglutition
swallowing
what is the purpose of the uvula
swings back to cover opening of nasopharynx to prevent food from going into it
what is the role of the soft palate in deglutition
swings upward to keep food from entering the nasopharynx
what is the function of canine
tearing or slashing
what can the autonomic nervous system influence
the enteric nervous system
the enteric nervous system is influenced by
the parasympathetic and sympathetic nervous systems
why would the epithelium of the gums and the epithelium overlying the hard palate be partially keratinized stratified squamous epithelium
they are regions exposed to severe abrasions
what type of tissue is found in the muscularis mucosa
thin layer of smooth muscle (stratified squamous)
what is unique about the muscularis externa that helps the esophagus perform its function
top 1/3 skeletal muscle for voluntary control of deglutition bottom 2/3 inner circular and outer longitudinal = involuntary (peristalsis)
which cranial nerve are involved in mastication
trigeminal
where is the sublingual gland located
under the tongue
the major parasympathetic nerve innervating GI organs is the
vagus nerve
the serosa is what type of serous membrane
visceral peritoneum
why is it significant that the upper esophagus contains skeletal muscle
voluntary control of degluition