Digestive system Flashcards
ingestion
process of bringing food into mouth
digestion
reducing food that you brought in body into its basic molecular building blocks
mechanical- physically breaking down food
chemical- in the intestines, food broken down into simplest form ; breaking chemical bonds
absorption
food brought across into body from GI tract
-food absorption takes place in small intestine, and some water absorption in large intestine
egestion
elimination/defecation/pooping/waste removal
dorsal cavity
cranial & spinal cavity
ventral cavity
thoracic & abdominopelvic cavity
peritoneum
surrounds organs in the abdominopelvic cavity
The mesentery that secures the small intestine is the:
mesentery proper
omenta
fold of peritoneum that connects stomach with another viscera
lesser omentum
runs from liver to lesser curvature of stomach
~functions to secure position of the stomach inferior to the liver
greater omentum
big flap that drops down from the stomach and covers the small intestine
~largest mesentery in the body; filled with adipose tissue
general fx of digestive system
to digest, mix, transport, and break down food
absorb nutrients, expel wastes
bolus
food mixed with saliva that goes down the digestive tract
chyme
stomach converts bolus into chyme
oral cavity
-teeth& tongue: mechanical digestion
-openings for salivary glands (chemical digestion start)
boundary-roof of mouth
oral cavity is lined by:
non-keratinized stratified squamous epithelium
pharynx
- nasopharynx (only part of respiratory system- airway)
- oropharynx- behind oral cavity; shared passageway for air and food
- laryngopharynx; connects to esophagus; broad opening into trachae; during swallowing, food has right of way not air.>stomach.
Oro & Laryngopharynx have non-keratinized stratified squamous epithelium
-pharyngeal constrictors- peristalsis, constrict to help propel bolus downwards
4 tunics of GI tract in order
Mucosa- innermost
Submucosa
Muscularis
Serosa/adventitia
Mucosa
-inner epithelium (tissue varies)
-underlying areolar CT called Lamina Propria
-thin layer of smooth muscle called muscularis mucosa
Submucosa
arealor or irregular dense CT binds mucosa to the muscularis
-mucin secreting glands to protect digestive tract against digestion
muscularis
2 layers of smooth muscle
-inner circular layer which contracts like a sphincter to help push food
-outer longitudinal layer shortens the tube; mixing food
serosa/adventitia
arealor CT with collagen and elastic fibers; if covered with visceral peritoneum then called Serosa, if not than it is adventitia
esophagus
conducts food inferiorly through thoracic cavity down into the stomach
-has all 4 tunics/layers
-made of skeletal & smooth muscle
stomach
upper left quadrant of the abdomen
-continues mechanical and chemical digestion of bolus
-bolus is processed into chyme
-temporarily stores food
4 regions
- cardia- entryway where esophagus meets stomach
- fundus- superior, lateral part; dome
- Body; largest part
- pylorus- exit region/funnel
Has greater (inferior) and lesser (superior) curvature
small intestine (3 parts) & function
made of the
-duodenum
-jejunum
-ileum
DJ Ileum
Fx: primary site of chemical digestion and nutrient absorption; secretes additional enzymes & mucus
duodenum
1st segment of small intestine; short
-receives secretions from pancreas and liver ; neutralizes acidic chyme
-mucosa : simple columnmar epithelium;; organized into vili
-submucosa: glandular structures, duodenal glands- submucosa/runner glands secrete an alkaline fluid
jejunum
-final stages of chemical digestion & majority of nutrient absorption
-mucosa: simple columnar epithelium;; pronounced villi where absorption takes place
-submucosa- nothing interesting here
lleum
-final stages of nutrient absorption
-mucosa: simple columnar epithelium; copious goblet cells; organized into villi
-submucosa: large purple lymph nodules (peyer’s patches)
Large intestine function
-absorbs most of water and ions from remaining material
-solidifes and stores feces
Cecum- food comes in and comes out in lower right quadrant of abdomen
Vermiform appendix (appendix)- important in immune regulation; storing bacteria
Ileocecal valve- prevents microbes from traveling from large to small intestine
Large intestine components [3]
Cecum- food comes in and comes out in lower right quadrant of abdomen
Vermiform appendix (appendix)- important in immune regulation; storing bacteria
Ileocecal valve- prevents microbes from traveling from large to small intestine
The region of the GI tract where the majority of absorption takes place is the:
small intestine
liver
largest abdominal organ (3.5 lbs) ; has 4 lobes
-refines blood from the digestive tract & secretes material to be removed from body
gallbladder
temporarily stores bile produced in liver
-green
-receives bile from hepatic ducts
-right and left hepatic ducts join to form the common hepatic duct, which drains the gall bladder
pancreas
large exocrine/endocrine gland secreting hormones to control blood sugar
secretes pancreatic juice [digestive chemicals and enzymes] to help with digestion
99% of cells are acinar cells = exocrine
1% is endocrine cells [release insulin & hormones]
identify 8
submucosa
The cell type that produces pepsinogen in the stomach is the:
chief cell
identify 16
the longitudinal layer of the muscularis externa
The sphincter that controls the rate of emptying of the stomach is the:
pyloric sphincter
The tunic of the GI tract that is responsible for peristalsis is the:
muscularis externa
The ____ are double sheets of peritoneal membrane that hold some of the visceral organs in position.
mesenteries
The mesentery that hangs from the inferior stomach is the:
greater omentum
Most of the chemical digestion & absorption of our food occurs within the:
small intestine
The main pancreatic duct merges with the _____, and their contents empty into the duodenum through the major duodenal papilla.
common bile duct
Which one of these organs is retroperitoneal?
pancreas
stomach
transverse colon
ileum
pancreas
Material leaving the ascending colon next enters the:
transverse colon
The _____________ cells of the stomach secrete hydrochloric acid (HCl).
parietal
Which organ is found in the upper right abdomen?
liver
spleen
vermiform appendix
descending colon
liver
function of circular folds
increase surface area of small intestine
what attaches the liver to abdominal wall?
falciform ligament
what restricts chyme entry into small intestine?
pyloric sphincter
haustra
sacs of large intestine wall
peristalsis
process to propel materials thru GI tract
which is the epithelium lining the small intestine?
simple columnar
which is the epithelium lining the esophagus?
stratified squamous
Peyer’s patches
lymphatic nodules in the wall of the ileum
-responsible for monitoring making sure bacteria not making wrong way into small intestine from large intestine
To tell the 3 regions of the small intestine apart, the most important tunic to look at is the:
submucosa
[most differences]
salivary glands
3 glands?
primary function?
- parotid salivary gland [25% of total saliva]
- submandibular salivary gland [70%]
- sublingual salivary glands [mucus secretions]
Primary Fx: moistens mucus membrane and start the breakdown of carbohydrates
papillae [tongue]
function?
4 types?
bumps on tongue
-increase surface area on tongue
circumvallate
fungiform
foliate
filiform
foliate & fungiform, & circumvallate papilla house:
taste buds
-contained modified cilia that allow sense of taste
-filiform papilla do not have taste buds
what goes on inside the buccal cavity?
3 pairs of salivary glands (6 total)
-produces up to 1.5 liters of saliva daily (majority water)
Alimentary canal is the-
digestive tract
around how long is the digestive system?
~30 foot long, open-ended, muscular tube
How many teeth does one have?
32
in the buccal cavity, __________________ breaks down starch
salivary amylase
the stomach serves to digest the bolus by adding:
enzymes (pepsinogen) and acids (hCl) to bolus, which becomes more liquid = chyme
fauces
opening into oropharynx
falciform ligament
double fold of peritoneum dividing liver into right and left halves; secures liver to diaphragm and posterior abdominal wall
mesentery proper
present between small intestine and dorsal body wall; numerous blood vessels
mesocolon
mesentery anchoring the large intestine (colon) to the dorsal body wall
diaphragm
forms the cranial wall of the abdominopelvic cavity
~essential muscle in the process of effective respiration; upon inhalation, it contracts and flattens, & thoracic cavity enlarges
Has a CENTRAL TENDON- thin and strong aponeurosis into which diaphragm muscle fibers insert with 3 openings
The 3 parts of the central tendon [of the diaphragm]
- vena caval foramen
- esophageal hiatus
- aortic hiatus
the gall bladder is filled and drained by:
cystic duct
the cystic duct and the common hepatic duct merge to form the:
common bile duct
The common bile duct drains:
bile from liver and gall bladder to duodenum
spleen
dark red structure lying along lateral curving surface of stomach; oval; left side of abdominal cavity
Function: to remove old/abnormal blood cells from circulation, begin hemoglobin metabolism; stores iron; initiates immune responses
[no actual digestive function but close to digestive structures…]
identify the cecum, sigmoid, ascending, transverse, and descending colon
Absorption of ___________ is a function of the digestive system.
nutrients
In the above image, the letter C indicates:
uvula
In the above image, the nasopharynx would be found at:
14
In the above image, C is the:
F is:
C: parotid salivary glands
F: submandibular salivary gland
identify this
Esophagus
identify this area
what feature would you find here?
stomach; gastric pits
identify this area
ileum
Identify this-
& what structure do you see?
Ileum
[note peyer’s patch]
identify this area
what do you see here?
Jejeunum
~ has long villi
Identify this area
what do you see?
Duodenum
~has villi
~mucosa, submucosa, muscularis externa layer
Identify this & what do you see here?
Stomach mucosa
~gastric pits on top/edge
~gastric glands in the middle edge (above submucosa)
Gastric glands- what 3 cells do they contain and what each do they secrete?
Chief cells - pepsinogen: breaks down proteins
Parietal cells - Hcl: stomach acid
Enteroendocrine cells - secrete digestion regulation hormones
Identify this area
[mucosa has which tissue type?]
Esophagus
[mucosa with stratified squamous epithelium]
Identify the left and right structures
left- trachea
right- esophagus
Round ligament
a remnant of the fetal umbilical vein
Rugae [of stomach]
the ridged lining of the stomach
Identify this
what is the arrow pointing to?
Duodenum
Arrow pointing to: Duodenal (Brunner’s) glands
Identify this region
Jejunum
Identify this
what is the arrow pointing to?
Ileum
Arrow pointing to: Peyer’s patches (Lymph nodules)
Identify this
what is the arrow pointing to?
Stomach
Arrow pointing to: Gastric pits/glands
Identify this region
Esophagus
The innermost tunic of the GI tract is:
mucosa
Describe the trachea’s epithelium
ciliated pseudostratified columnar
The liver is an ___________ organ
accessory
The structures in the larynx that vibrate to produce sound:
vocal folds
the sphincter controlling the emptying of the stomach is:
pyloric sphincter
the outermost tunic of the GI tract is the:
serosa/ adventitia
Identify this + what is the arrow pointing to
Stomach; Gastric pits
Identify this + what is the arrow pointing to
Ileum; Peyer’s patches
Identify this + what is the arrow pointing to
Duodenum; duodenal glands
Identify this region
Jejunum
Identify this region
Esophagus
Identify this + what is the arrow pointing to
Central tendon of the diaphragm
Identify this
diaphragm
Identify this
diaphragm
Identify this organ, A, B, C, and D
Liver
A- right lobe
B- left lobe
C- falciform ligament
D- gallbladder
Identify A, B, C
A- common hepatic duct
B- cystic duct
C- common bile duct
Identify A, B, C
A- common bile duct
B- common hepatic duct
C- cystic duct
Identify A
Pancreas
identify A
Spleen
identify
parotid salivary gland
identify
sublingual salivary gland
identify
submandibular salivary gland
identify the papillae on the back/ side of the tongue
Foliate papillae
identify these papillae (posterior, v-shaped row of 8-12)
Circumvallate papillae
Filiform papillae lack:
taste buds
Identify A, B
A- Filiform papillae
B- Fungiform papillae
identify the green
greater omentum
what is the red arrow pointing to?
falciform ligament
what is the red arrow pointing to?
falciform ligament
identify the green
round ligament
identify circled areas
mesocolon
A and B are:
A- mesocolon
B- mesentery proper
Identify all parts
A- pylorus
B- cardia
C- fundus
D- rugae (folds)
E- pyloric sphincter
identify the green
stomach
identify the green
body of stomach
identify the green
small intestine
identify small intestine regions by color
yellow- Duodenum
purple- jejunum
pink- ileum
identify the green (bottom)
appendix
identify highlighted area
cecum of colon
what is it circling?
haustra
thin bands of muscle around the large intestine that produce haustra are-
taeniae coli
Identify A, B, C
A- ascending colon
B- transverse colon
C- descending colon
Greater VS lesser curvature of stomach
Vestibule of mouth
space between teeth/lips/cheeks
Palatine tonsils
large aggregations of white blood cells involved in immunity/ infection recognition
[pair of palatine tonsils; 5 total tonsils]
Fauces
latin=throat
opening into pharynx
identify top structure [white]
hyoid
Cecum
pouch/large tubelike structure in the lower abdominal cavity that receives undigested food material from the small intestine
~1st region of the large intestine.
~separated from the ileum by the ileocecal valve, which limits the rate of food passage into the cecum and may help prevent material from returning to the small intestine.
Vermiform appendix (appendix)
important in immune regulation; storing bacteria
Ileocecal valve
prevents microbes from traveling from large to small intestine
which salivary gland secretes the most mucus?
submandibular salivary glands (70%)
the opening into the oropharynx is the-
fauces
the cystic duct fills and drains :
the gall bladder
segmentation/mixing is
churning of chyme
serous membrane covering the muscularis externa is
serosa
chewing is _________ digestion
mechanical
what produces and stores secretions?
accessory organs
The tunic of the GI tract that is responsible for peristalsis is the:
muscularis externa
submucosa contains which tissue
dense irregular CT and blood vessels
Pancreatic juice is produced by :
the acinar cells of the pancreas
Pancreatic juice has a ___________________ pH
alkaline
pancreatic juice is secreted through the ________ and into the _______________
main pancreatic duct and into the duodenum
