Digestive System Flashcards
what is the purpose of the digestive system?
acquire nutrients and water
___ and ____ are absorbed through the stomach
alcohol, aspirin
___, __ ____, and ____ are absorbed through the small intestine
glucose, amino acids, fats
sodium, potassium, acids, bases, calcium, magnesium, iron, vitamin B12, and water are absorbed where?
large intenstine
nutrients are passed into ____ of the digestive system and transported to the _____
veins, liver
fats are absorbed in the __ ____ and then passed into the ____ _____
small intestine, lymphatic system
what do fats pass through from the small intestine to the lymphatic system?
lacteal duct
in the ends, fats eventually enter the __ _____
circulatory system
the ____ ____ is the storage site for feces
sigmoid colon
____ is taking food into the mouth
ingestion
____ is swallowing and peristalsis
propulsion
_____ is voluntary propulsion
swallowing
____ is involuntary movement of food
peristalsis
chemical digestion occurs in the ___, ____, and __ ____
mouth, stomach, small intestine
_____ is the transporting of nutrients, electrolytes, and water into the veins and fats into the lymphatic system
absorption
_____ is the elimination of indigestible substances
defecation
the intestine contains circular and longitudinal __ ____
smooth muscle
peristalsis utilizes the ___ ___ of the intestines to propel food through the lumen
smooth muscle
____ utilizes smooth muscle to mix rather than propel
segmentation
what is the histological organization of the entire length of the GI tract?
mucosa, submucosa, muscularis externa, adventitia
what are the 3 components of mucosa?
true epithelia, lamina propria, muscularis mucosae
arteries, veins, nerves, lymphatics, and mucus glands are housed in what layer of the histology of the GI tract?
submucosa
what is muscularis externa made of?
smooth muscle
what are the 2 layers of the muscularis externa?
inner circular, outer longitudinal
the ___ ___ ____ signals submucosal glands to secrete and muscularis mucosae to contract
submucosal nerve plexus
where is myenteric located?
between circular and longitudinal layers of the muscularis externa
____ controls peristalsis and segmentation
myenteric
what are the 4 categories of mucus membrane?
protective, secretory, absorptive nutrients, absorptive water and electrolytes
what type of cell is the protective mucus membrane?
stratified squamous
where is protective stratified squamous mucus membrane found?
oral cavity, pharynx, esophagus, anus
what type of cell is the secretory mucus membrane?
simple columnar
what is simple columnar secretory mucus membrane found?
stomach as mucus secreting and mucus neck cells
what type of cell is nutrient absorptive mucus membrane?
simple columnar
where is absorptive simple columnar mucus membrane found?
small intestine
what type of cell is water and electrolyte absorptive mucus membrane?
simple columnar
where is water and electrolyte simple columnar mucus membrane found?
large intestine
the ___ _____ is the line between the tooth and gums
alveolar ridge
the ____ is the space between the lip and alveolar ridge
vestibule
___ _____ is the fold of the lip to the gum
labial frenulum
_____ _____ is the fold off the tongue to the floor of the oral cavity
lingual frenulum
salivary glands open into the oral cavity ___ ___ _____ and ___ ___ ____
under the tongue, through the cheek
what is the roof of the oral cavity made up of?
soft and hard palates
the ____ dangles down from the soft palate
uvula
what muscle forms the lips?
orbicularis oris
what muscle forms the cheeks?
buccinator
what are the lateral arches of the soft palate?
palatoglossal and palatopharyngeal arches
the palatoglossal arch extends from ___ to ____
palate, tongue
the palatopharyngeal arch extends from ___ to ____
palate, pharynx
what is located between the two lateral arches of the sold palate?
palatine tonsil
the tongue is covered with _____
papillae
what are the 3 filiform on the tongue?
filiform papilla, fungiform, circumvallate
____ ____ of the tongue resemble pointed cones, are the most numerous, and have no tastebuds
filiform papilla
____ of the tongue resemble mushrooms and possess tastebuds
fungiform
_____ of the tongue resembles a circular wall and possess tastebuds
circumvallate
____ _____ separates the circumvallate papilla and lingual tonsil
sulcus terminalis
____ is the opening between the oral cavity and the oropharynx
fauces
palatoglossal arch, uvula, and sulcus terminalis are the borders of what opening?
fauces
___ ___ is the ring of protective tonsils in the oropharynx
tonsilar ring
what is the tonsilar ring composed of?
palatine and lingual tonsils
___ ____ produce and deposit saliva into the oral cavity
salivary glands
the serous cells of the parotid gland secrete ____ and ____
amylase, lysozymes
what does amylase digest?
carbohydrates
the parotid duct passes through what muscle?
buccinator
the sublingual gland’s cells secrete _____
mucus
the parotid gland secretes ____
serous
the submandibular gland secretes what?
serous and mucus
how many teeth are there?
32
there are 2 _____ for cutting food in the mouth
incisors
there is 1 ____ for shearing and tearing
cuspid/canine
there are 2 ______ that precede molars
bicuspid/premolars
there are 3 ____ to mill or grind
molars
the _____ carries bolus from oral cavity to stomach
esophagus
what type of cell is found in the esophagus?
stratified squamous (protection)
___ ____ transitions from skeletal to smooth in the esophagus
muscularis externa
as the bolus passes through the glands, ____ is secreted for lubrication
mucus
into the diaphragm, the esophagus passes through the ___ ____
esophageal hiatus
muscles fibers of the diaphragm act as the primary sphincter muscles of the esophagus and are referred to as the ___ _____
cardiac sphincter
the stomach completes ____ and ____ digestion
chemical, mechanical
the ____ sphincter prevents food from leaving the stomach
pyloric
what are the 4 parts of the stomach in order?
cardiac, fundus, body, pyloris
what are the superior and inferior surfaces of the stomach called?
lesser (superior) and greater (inferior) curvatures
____ are the folds of the stomach that occur when the stomach shrinks and is empty
rugae
what are the 3 layers of the stomach’s muscularis externa (made of smooth muscle)?
innermost oblique, middle circular (thick), outer longitudinal
the pyloric sphincter is formed from what layer of the stomach’s muscularis externa?
middle circular
what type of cells line gastric pits?
simple columnar cells called mucus secreting cells
___ _____ cells secrete mucus and line of the gastric pit
mucus neck
where are stomach gastric glands located?
the gastric pits of the fundus and body
what is excreted by parietal cells of the stomach?
HCl for the hydrolysis of proteins
what PH does HCl make the stomach?
2
what is excreted by chief cells of the stomach?
pepsinogen
pepsinogen+HCl=
pepsin (protease)
what is pepsin used for in the stomach?
break down proteins
what is secreted by endocrine cells of the stomach?
hormone gastrin
when food enters the stomach, what hormone is produced?
gastrin
what is the role of gastrin in the stomach?
stimulate parietal cells to excrete HCl and chief cells to excrete pepsinogen
what regions of the stomach produce the two types of mucus?
all
what regions of the stomach have parietal and chief cells?
fundus and body
what is released by the endocrine cells of the stomach?
insulin, glucogon
what type of cells excrete HCl and pepsinogen in the stomach (exo or endo)?
exocrine
exocrine chemicals travels through a _____ to a _____
duct, lumen
endocrine hormones travel in the _____ to ___ _____
blood, other cells
what is absorbed by the small intenstine?
nutrients (glucose, vitamins, fats)
what are the 3 parts of the small intestine in order?
duodenum, jejunum, ileum
the duodenum begins after the ___ sphincter
pyloric
the ilium ends at the ____-_____ valve
ilio-cecal
what histology of cells are good for nutrient absorption?
simple columnar
_____ are macroscopic finger-like projections of the mucosa in the small intestine
villi
______ are microscopic folds on the apical surface of cells of the small intestine
microvilli
___ __ ______ are located in between adjacent villi of the small intestine
crypts of lieberkuen
___ cells are located at the bases of the crypts of lieberkuen and secrete lysozymes
lysozymes
__ ____ are aggregated lymphoid nodules found in the small intestine that are MALT
peyer’s patches
___ ____ are specialized ducts of the lymphatic system to carry fats
lacteal vessels
___ cells transfer emulsified fats into lacteal ducts
absorptive
goblet cells secrete ____
mucus
what are the two layers of the muscularis externa in the small intestine?
inner circular, outer longitudinal
_____ ____ are the mucus secreting cells in the submucosa of the duodenum
brunner’s glands
submucosal cells are located in what two parts of the digestive system?
esophagus, duodenum
what two hormones are secreted when food enters the duodenum?
CCK (cholecystokinin) and secretin
Hormone CCK signals the _____ to contract and release ___ into the duodenum
gallbladder, bile
Hormone secretin signals the _____ to excrete ___ ____ into the duodenum
pancreas, digestive juices
what is absorbed by the large intestine?
water, electrolytes (sodium, potassium, acids, bases, vitamins
what are the parts of the large intestine in order?
cecum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum
the large intestine begins at the ___-_____ junction
ileo-cecal
the ileo-cecal valve is a sphincter formed from what layer of the muscularis externa?
circular
at what point does the ascending colon become the transverse colon?
hepatic flexure