Digestive system Flashcards
When it comes to binding of Immunglobin A to non cell mediated it is called
oppsinization
How many tastes of the tongue and what are they
5 Tastes Sour Bitter Salty Unami Sweet
What are the cells in the Stomach and there functions
Chief Cells: and Pepsin
PARIETAL CELLS: Secrete gastric Acid
Neck Cells: Mucous epithelial cells function unkown
G Cells: Cells in stomach and duodenum that releases Gastrin
STEM Cells:
Name all the sphincters in the Digestive System and function
Lower esophageal or cardiac: sphincter between esophagus and stomach.
Pyloric Sphincter: between stomach and duodenum.
Ileocecal Sphincter between small intestine and caecum
Anal Sphincter at end of rectum.
Upper esophageal. Sphincter between mouth and esophagus.
How many IG What are all the Immunoglobins function?
Ig A: mucous glands like salivary tears sweat glands etc
Ig E: In Milk
Ig D: On red Blood cells Rhesus
Ig M: Pentomer on MHC on Lmphyocytes
Ig G: Free floating antibodies made by B Cells
How many layers and function of the layers of The gastrointestinal walls
Mucosa: Epithelia cells
Submucosa:
Muscularis: Shortening and or Walls
Serosa/ Advantitia
What is the criteria to being an epithelia Cell
Free surface Cell
Densely Packed
Avascular
Polarized/Nonsemetical aka has an apical and basal side
3 Things needed to be classified as a mucosa are
Must have
Epithelial cells
Basement Membrane
Mucosa Muscularis
The smooth muscle cells that form the foldings and contraction of the small intestine called
Mucosa Muscularis
The inner lining of the digestive tract, called the
mucosa or mucousmembrane
The epithelium of the digestive system is majority ___ except for where?
simple columnar in everywhere but esophagus and anal cavity where it is stratified squamous to protect against abrasion
The digestive tract as a whole is made up of
mucosa/ columnar epithelium
loose connective tissue called lamina propria
and smooth muscle tissue called muscularis
what does the submucosa consist of
aerolar tissue
nerves and vasularities
fiber created by fibroblasts
What is the Enteric Nervous System and what is it a subdivision for
the submucosal plexus in the submucosa and
the myenteric plexus
True /False Salivary glands is controlled by the parasympathetic nervous system?
false its controlled by the sympathetic NS
What are the two network of neurons in the enteric system and what are there functions
Submucosal plexus: plexus controls movements of the muscularis mucosa and glandular secretion
Myenteric plexus: controls peristalsis and other contractions of the muscularis externa,
The foldings in the stomach are know as..
Ruge
what is the Largest fold in the small intestine know as?
What are the characteristics?
Semicircular Pilae
Glands involved in Digestion
Sublingual Submadibular
5 stages of Digestion and function
Ingestion Digestion Absorption Compaction Excretion
what is syncytium and what cells are examples of this
Are multinucleated structures such as skeletal muscles and osteoclasts
define the 2 types of syncytium
True actually have multiple nucleated cells
Functional only act example
myocardiocytes couple with gap junctions act as a multinucleate group
segmental contraction is
where does it occur
contraction that mixes up chyme
occurs in the small intestine
the three parts of the small intestine in order are
the Duodenum
the Jejunum
the Ileum
In simple terms define Peristalsis
Wave like contractions
what are the two types of contractions
Peristalsis and Segmental Contractions
How many glands and functions are in the digestive system
sublingual
submandibular
Parotid
What is transducin
G couple protein receptor that reponses to sweet chemicals
T or F Gaba is release with to stop cl inflow in b cells
false GABA allows cl flow into alpha cells to hyperpolarize alpha cells preventing calcium for entering and releasing glucagon
T or F Glucagon and Insulin can both be released at the same time
False GABA Prevents that
What happens when Transducin is excited or binded to
G coupled protein receptor
alpha protein activates
what are the two most important ions
Hydrogen and potassium
what is the role of potassium in the body
Potassium regulates the resting membrane potential
what are the three large main layers of the digestive system
mucosa
submucosa
muscularis externa
serosa/adventia
what layers create the mucosa
Epithelium
lamina propria
muscularis mucosae
Which epithelium are in which cavities of the digestive system
stratified squamous are in the mouth and esophagus and lower anal canal for help against abrasion
Ciliated Columnar for the small and large intestine
where is the lamina propria and whats its role and the cells involved
its between the epithelium and muscularis mucosae and its a connective tissue with fibroblasts
Role of the muscularis mucosae
The muscularis mucosae tenses the mucosa, creating grooves and ridges that enhance its surface area and contact with food
Main role of the submucosa
The submucosa is a thicker layer of loose connective tissue containing blood vessels and lymphatics, a nerve plexus, and in some places, glands that secrete lubricating mucus into the lumen. The MALT extends into the submucosa in some parts of the GI tract.
Define the muscularis externa
The muscularis externa consists of usually two layers of muscle near the outer surface. Cells of the inner layer encircle the tract while those of the outer layer run longitudinally.
The enteric Nervous system controls which organs
he esophagus, stomach, and intestines
which nerve controls peristalsis and muscularis exeterna
myenteric NS
WHat does the submucosal plexus innervate?
glandular and muscularis mucosae
hey are not tightly bound to the abdominal wall,
but over most of their length, they are loosely suspended from it by connective tissue sheets called
mesenteries
what is a mesenteries and what is it made up of
Mesenteries is connective tissue that hold the abdominal viscera in their proper relationship to each other, provide passage for the blood vessels and nerves that supply the digestive tract, and contain many lymph nodes and lymphatic ves- sels.
which organs lie on the retroperitoneal side ?
The duodenum
most of the pancreas
parts of the large intestine are retroperitoneal.
which organs lie on the intraperitoneal side ?
Stomach,
liver,
parts of the small and large intestines are intraperitoneal
What is the parietal peritoneum
parietal peritoneum is a serous membrane that lines the wall of the abdominal cavity.
what is a serous membrane? where are the serous membranes in the body?
mesothelial tissue that lines certain internal cavities of the body, forming a smooth, transparent, two-layered membrane lubricated by a fluid derived from serum. The peritoneum, pericardium, and pleura are serous membranes.
wiki definition of mesentary
mesentery: The membrane that attaches the intestines to the wall of the abdomen and maintains their position in the abdominal cavity to supply them with blood vessels, nerves, and lymphatics.
T/F Omentum comes from peritoneum
true it does come from peritoneum
whats the difference between Omentum and messentary
Omentum peritoneum with fat covers both sides of stomach with peritoneum. acts as insulation.
T/F: the liver is on the left side of the body and is above the stomach
False Liver is on the right side and sits slightly above the stomach
what organs are right below the stomach?
Large Intestine
The 3 mechanisms that control the motility and secretion of the digestive system are
Hormonal
Paracrine
Nervous systems
Roles of Saliva are
Saliva moistens and cleanses the mouth, inhibits bacterial growth, dissolves molecules so they can stimulate the taste buds, digests a little starch and fat, and makes swallowing easier by binding the food particles into a soft mass (bolus) and lubricating it with mucus.
the compounds in saliva are
∙ mucus, which binds and lubricates the food bolus;
∙ electrolytes, salts of Na+, K+, Cl–, phosphate, and bicarbonate;
∙ lysozyme, an enzyme that kills bacteria;
∙ immunoglobulin A (IgA), an antibacterial antibody;
∙ salivary amylase, an enzyme that begins starch digestion in the mouth; and
.ligual Lipase
amylase is an enzyme which function is to
hydrolyze or break starch to simple sugar with water
Roel of Intrinsic Salivary Glands
They secrete saliva at a fairly constant rate whether we are eat- ing or not, but in relatively small amounts. This saliva contains lingual lipase and lysozyme and moistens the mouth when we are not eating.
what are the glands in the extrinisic salivary glands and there roles
Parotid
submandibular
sublingual
what is responsible for the folds of the cavities in the digestive system
muscularis mucosae in the mucosa
largest fold of the small intestine are?
what is the role?
Semicircular pilcae which contain microvilli
the spin chyme to allow brush borders to become more efficient
What are the steps for insulin release
Pancrease detects high blood sugar through elevate atp
ATP closes leaky k+ channels elevates MP
B Cells release insulin and GABA
GABA blocks glucagon release by hyperpolarization
what products do gland acini add to saliva
amylase, lingual lipase, lysozyme and mucus
Role of pharynx
muscular funnel connects
oral cavity to the esophagus
nasal cavity to larynx
T/F The pharynx is where digestive and respiratory tracts intersect
True
where the esophagus penetrates the diaphragm is called
esophageal hiatus
Role of the Lower esophageal sphincter (LES)
prevents stomach contents from regurgitating into the esophagus, thus protecting the esophageal mucosa from the erosive effect of stomach acid.
failure of the Lower esophageal sphincter/cardiac sphincter can lead to
Heartburn
esophageal glands are located where in the esophagus?
submucosae
whats the name of swallowing and the 3 phases of
swallowing also known as deglutition
phase one oral phase
phase two pharyneal phase
phase three esophageal phase aka perisastalsis
whats the name of swallowing and the 3 phases of
swallowing also known as deglutition
phase1 oral phase
phase2pharyngeal phase
phase 3 esophageal phase aka peristalsis
In what phase of deglutition is breathing suspended
pharyngeal phase
Peristalsis is controlled jointly by what parts of the CNS?
Brainstem and Myenteric plexus
T/F
Most digestion occurs after the chyme passes on to the small intestine.
True
Name 4 regions of the stomach
The cardial part (cardia)
The fundic region
The body (corpus)
pyloric part
Define pylorus
narrow passageway leading to duodenum
T/F The stomach ONLY recieves stimulation from the parasympathetic nervous system
False
parasympathetic fibers from the vagus nerves
sympathetic fibers from the celiac ganglia
where does blood flow after duodenum and stomach
To the hepatic portal vein at the liver
T/F both esphophagus and stomach are lined with stratified squamous epithelium on there mucosa
False
esophagus lines with stratified squamous
Stomach lined with columnar glandular epithelium
T/F The apical regions of epithelium of the stomach cells are filled with mucin; after it is secreted, mucin swells with water and becomes mucus
True
How many layers does the muscularis externa have?
3 compared to the 2 the others have
what are the 3 glands present in the stomach
Gastric Glands
plyoric glands
cardial glands
What are the cells present in the three glands
Chief cells: secrete enzymes gastric lipase and pepsinogen
parietal cells: Secrete Gastric acid/ hcl ,intrinsic factor and grehlin
Mucous cells: Secrete mucus
Enteroendocrine cells
Regenerative stem cells: Replace old cells
How does stomach sustain low ph without being damaged
Parietal cells contain carbonic anhydrase (CAH)
H+–K+ ATPase. is what type of transporter and where is it located
Its an antiporter located in parietal cells
What is the role of stomach acid?
activates pepsin and lingual lipase,
It breaks up connective tissues and form chyme.
turns ferric ions (Fe3+) to ferrous ions (Fe2+), for hemoglobin synthesis.
innate immunity destroying most ingested pathogens.
T/F Pepsin has autocatalytic effect?
True
as some pepsin is formed, it converts pepsinogen into more pepsin
what is gastric lipase where is it secreted from
Secreted from chief cells gastric lipase digest 10-15 percent of the fats in the stomach
How is Vitamin b12 absorbed and low amounts result in?
Absorbed by Small Intestine when “Intrinsic Factor is released by parietal cells
Needed for hemoglobin synthesis without it can lead to anemia
T/F The secretion of intrinsic factor is NOT the only indispensable function of the stomach
False it is
what is and the cause of Pernicious anemia
Anemia cause by low production of Vitamin B12 because of autoimmune disease that destroys gastric mucosa
When swallowing mechanoreceptors where? send signal to wat part of the CNS
mechanoreceptors in the pharynx and they transmit signals to the medulla oblongata.
the medulla relays signals to the stomach by way of the VAGUS NERVE.
what are the secretions/hormones of the enteroendocrine cells
Gastrin: Stimulates intestine motility and gastric glands to secrete HCl and enzymes Serotonin: Stimulates gastric motility Histamine: HCL secretion Somatostatin Gut–brain peptides
How does the stomach protect itself from its own acidic environment
Mucus coat
Tight Junctions
Fast Epithelial cell replacement by cell division in gastric pits
Gastric activity is divided into what three phases
cephalic: stomach responds to mere sight, smell, taste, thought of food
40% of the stomach’s acid secretion
gastric: Histamine is a paracrine secretion from enteroendocrine cells in the gastric glands.
intestinal phases
Which three hormones cause parietal cells to release HCL
ACH by parasympathetic nerve fibers
Histamines by enteroendocrine aka G-cells
Gastrin by enteroendocrine cells aka G-cells
What chemicals causes chief cells to release Pepsinogen
Gastrin and especially ACH
digested proteins from breakdown in the stomach cause a POSITIVE OR Negatiive feedback to WHAT?
Causes a positive feedback to G cells
PH required to inhibit parietal cells
PH of 2
glucose-dependent insulinotropic peptide (GIP).
weak gastrin inhibitory hormone that stimulates insulin release
Chyme in the Duodenum stimulate intestinal G cells to secrete?
CCK and Secretin
All nutrients absorbed by the small intestine reach the liver except
Fats which use the lymphatic system
hepatic triad consists of
Hepatic artery
Hepatic portal vein
Bile duct
T/F
About 99% of the pancreas is endocrine tissue
False
About 99% of the pancreas is exocrine tis- sue, which secretes 1,200 to 1,500 mL of pancreatic juice per day
The
trypsinogen
chymotrypsinogen
procarboxypeptidase
The pancreatic enzymes from pancreas are
pancreatic amylase, which digests starch; pancreatic lipase, which digests fat; and ribonuclease and deoxyribonuclease,
What are Acinar cells
Are pancreatic exocrine cells that secrete digestive enzymes
Name all secretions of the pancreas
Sodium Bicarbonate. Neutralizes HCL Zymogens trysinogen, Chymotrypsinogen, Procarboxypeptidase Pancreatic amylase: breaks down starch Pancreatic lipase: Breaks down lipids Ribonuclease Deoxyribonuclease
What three stimuli responsible for release of pancreatic juices and bile
ACH AND SECRETIN EFFECTS PANCREASE
ACH comes from vagus nerve during cephalic phase
SECRETIN: from duodenum cause sodium bicarbonate release
CCK EFFECTS GALLBLADDER
induces contractions
duodenal papillae
wrinkles and grooves in the small intestine where pancreatic duct binds to
What are some key activities that occur in duodenum
Stomach acid is neutralized here,
Fats are physically broken up (emulsified) by the bile
Pepsin is inactivated by the elevated pH,
Pancreatic enzymes take over the job of chemical digestion
What are key activities that occur in the jejunum
Where most of the absorption occurs
The ileocecal valve and its functions
The ileocecal valve is a sphincter muscle valve that separates the small intestine and the large intestine.
Where does the small intestine receive all its blood from?
superior mesenteric artery,
The jejunum and ileum are retroperitoneal and intraperitoneal
The jejunum and ileum are intraperitoneal and thus covered on all sides with a serosa
tiny projections that give the inner lining of the intestine a fuzzy texture, like a terry cloth towel are called
Villi
a lacteal is
the lympathic capillaries in villi in the small intestine
Brush border are located where in S Intestine? and also participate in what type of digestion?
microvilli
Contact Digestion
The role of Duodenal glands is to
secrete bicarbonate mucus to neutralize acid
whats the difference btwn GLUT vs SGLT
Glucose Transporters (GLUTs) - are located in beta cells, hepatocytes, skeletal muscles, etc., to facilitate transport of glucose into the cells. Sodium-glucose co-transporters (SGLT 1 & 2) -in small intestine and renal tubules of nephrons, facilitating the reabsorption of glucose back into circulation.
ENTEROCYTES are ?
Enterocytes intestinal absorptive cells, are simple columnar epithelial cells found in the small intestine.
name of the inner and outer layer of muscularis externa
the inner circular layer
the Outer Longitudinal layer
T/F myenteric plexus is part of the sympathetic nervous system
False part of the parasympathetic
what is the myenteric plexus
A plexus of small groups of nerve cells (ganglia) and connecting nerve fibre bundles that lies between the longitudinal and circular muscle layers of the gut wall and forms a continuous network from the upper esophagus to the internal anal sphincter.
roles of vitamin D in Digestion
Vitamin D helps with calcium absorption which aids in hormones release to help digestion
what is the Plexus of Meissner
Another word for the submucosal plexus
T/F the lamina propria is not analogous to the dermis
F
it is analogous to the dermis and is connective tissue
what type of muscle is the muscularis mucosae
thin smooth muscle
what cells are present with epithelial cells in the esophagus
goblet cells which release mucus
and enteroendocrine cells
where are the lymphocytes embedded in the esophagus
in the lamina propria along with blood vessels and nerves
what is MALT
Mucosa associated lymphoid tissue
Define peyers patches
clusters of lymphoid tissue located at the end of the ileum
the folds in stomach and small intestine due to the
muscularis mucosae aids in increased surface area
glands are form starting where?
in the submucosae which is made out of dense connective tissue
T/F
most proximal and distal regions of the alimentary canal, including the mouth, pharynx, anterior part of the esophagus the muscularis is made up of skeletal muscle
True
T/F
anterior part of the esophagus is controlled by smooth muscle
False
controlled by skeletal muscle
what and where is the serosa of alimentary canal located?
serosa is loose connective tissue superficial to muscularis
only in the abdominal cavity
instead of serosa the mouth pharynx esophagus have what?
adventitia which is made of collagen
Intrinsic innervation of much of the alimentary canal is provided by which nerves?
enteric
the fight-or-flight or rest and digest response is governed by intrinisic or extrinisic
extrinsic innervation
The celiac trunk services which organs
Liver stomach duodenum
T/F Celiac trunk supplies the jejunum and colon
False
the superior and inferior mesenteric arteries do
The peritoneum is made up of what epithelium?
squamous surrounded by connective tissue
what are the 5 peritoneal folds
Greater omentum: apron flap for obese people
Falciform ligament: anchors liver
lesser omentum: stomach
mesentery: all small intestine except duodenum
mesocolon: tranverse sigmoid colon
what are retroperitoneal organs and which organs are they?
retroperioneal are organs r completely or partially posterior to the peritoneum
Includes pancreas, liver, duodenum ascending and descending colon retum
submucosal plexus
aka? what does it do
(plexus of Meissner) nerve supply that regulates activity of glands and smooth muscle
innermost lining of the alimentary canal
mucosa
labia are …
the lips
the 3 pharynx are called
naso
oro
laryngo
Deglutition is another word for
how many and what are the phases
swallowing
3 stages voluntary stage last two is autonomous pharyngeal phase esophogeal phase
Which of these ingredients in saliva is responsible for activating salivary amylase?
chloride
teeth are secured by…
alveolar processes aka sockets of mandible
hardest substance in the body is
enamel
the loose connective tissue that contains the blood vessels and nerves are called
pulp cavity
Dentin is…..
bone-like tissue surrounding the pulp cavity
Name the structures from outermost to inner of the tooth
Crown neck and Root Enamel Cementum Dentin Pulp cavity: vessels/Nerves
define pharynx
throat involved in both digestion and respiration
which part of pharynx is involved only in speech and respiration
nasopharynx
which part of pharynx is involved in digestion but not respiration?
none all are used for respiration
anterior portion of the Larynopharynx connects to ?
the trachea
What primary cells muscles are activated during the swallowing process
skeletal muscle of the pharynx expanding it relaxation narrows it causing bolus to go down
T/F the most superficial layer of the esophagus is called serosa
F
Called Adventitia
the large intestine technically has 2 layers, but the outer longitudinal layer is separated into three, narrow bands called
tenia coli
the enzymes present in the mouth
salivary amylase
lingual lipase
define each of oral cavity hard soft palates gingiva superior inferior labial frenulum vestibule uvula
hard soft palates: Roof of mouth
gingiva: The gums
superior inferior labial frenulum: attaches tongue to gums
vestibule: region between teeth and cheek
uvula: Oval process hangs down posterior portion oval cavity
The two pilae of the tongue
Fungiform: taste buds
filiform: abrasive surface for food
Tooth is anchored to the jaw bone by
peridontal ligament
what makes up the most structural mass of the mouth
dentin
T/F
food moves from the mouth into the Nasopharynx ,oropharynx, laryngopharynx, and then into the esophagus
• it is a closed tube
false does not move through nasopharynx
4 areas of the stomach
cardia
fundus
body
pylorus
3 regions of large intestine
cecum
colon
rectum
colon consist of how may sections and what are they
ascending colon transverse colon descending colon sigmoid colon
what part of the digestive system does the pancreas bind towards
duodenum
what how many cranial nerves are there
12
which cranial nerves does not go to the hypothalamus
cranial nerve 1 the olfactory
name all cranial nerves
olfactory
visual
346 are eye movements
cranial 5 is trigeminal nerves :pain and temperature of nerve
cranial nerve 7 (facial nerve)
cranial 9/10 are the swallowing /gag reflex
What are the two regions of the tongue
anterior 2/3
posterior 1/3
what is responsible for secretion of glands
muscularis mucosae
majority of blood vessels are located where in the cross section of stomach
submucosae
the inside of the stomach are line with what epithelial cells
simple columnar cells that produce mucus
how does the stomach knows it has food in it?
stretch receptors send signal to afferent nerves to vagus cranial nerves (cranial nerve 10)
what is release from parietal cells when activated
Hydrochloric Acid
intrinsic factor which absorbs vitamin b12
what factors cause parietal cells to release its compounds?
Activation of parietal cells of by vagus nerve release of acetlycholine
.Activation of parietal cell receptor by gastrin by g cells
.Gastrin binds to compound that releases histamine which . binds to receptor cell on parietal cell
how does parietal cells created hcl?
converts co2 and h20 to make carbonic acid which seperates to bicarbonate and h+ which is released into the stomach
metabolic akalosis
when blood is too basic seen in people in bulmenia
