NST 103 L1 UPDATED ACTUAL Exam
Questions and CORRECT Answers
5 compartments of the GI tract - CORRECT ANSWER - Oral cavity, esophagus, stomach,
small intestine and large intestine.
Name 4 accessory organs. - CORRECT ANSWER - Salivary glands, liver, gallbladder and
pancreas
Name at least 3 functions of the stomach. - CORRECT ANSWER - 1.Form chime
2.Store food
3.Secrete acid, pepsinogen & mucus
4.Initiates digestion of proteins and lipids
Kill bacteria
5.Absorb ethanol, some drugs and other small water-soluble compounds
What is secreted from G-cells - CORRECT ANSWER - Gastrin.
When G-cell release gastrin, it can go ECL cell to produce more histamine, or bind directly to the
parietal cell, and activiate cAmp.... The final goal is to stimulate more H+ pumping out
What is secreted from parietal cells - CORRECT ANSWER - Produce HCL and Intrinsic
factor (Absorb B12)
What is secreted from D cells - CORRECT ANSWER - Somatostatin
inhibitory the production of HCL
What is secreted from ECL cells(enterichromaffin-like cell) - CORRECT ANSWER - ECL
release histamine, then binds to H2 receptor
, What is secreted from Chief cells - CORRECT ANSWER - 1.pepsinogen(proenzyme), which
later on converts to Pepsin by HCL. Pepsin is an enzyme that breaks down protein to smaller
peptides.
2. Gastric Lipase splits fat (only remove one fatty acids but still)
What is Vagus nerve release? - CORRECT ANSWER - Vagus nerve release acetylcholine,
will either goes to ECL cell to produce histamine, or binds to acetylcholine (M) receptor.
summary diagram for HCL production in parietal cells - CORRECT ANSWER -
What is the main function of goblet cells? - CORRECT ANSWER - Mucin production
Name the 4 layers that comprise the wall of the gastrointestinal tract. What layer comes into
contact with food? - CORRECT ANSWER - 1. Mucosa
2. Submucosa
3. Muscularis
4. Serosa
*Mucosa is the layer that come into contact with food
Describe how parietal cells mediate acidification of the stomach. - CORRECT ANSWER -
step 1: CO2 diffuses into the cells, and the enzyme carbonic anhydrase catalyzes the reaction
between CO2 and water to form Carbonic Acid. H2CO3-.
Step 2: H2CO3 dissociates into bicarbonate ion (HCO3-) and H+.
Step 3: As HCO3- and H+ accumulates into the cell, HCO3- is ejected through the basal cell
membrane into the capillary blood by secondary active trans, in order to get CL- in
Step 4: ATP will then bind to the H+/K+ ATPase where the potassium knows are facilitated and
counter diffuse into the stomach lumen then come back into the parietal cell and exchange for
hydrogen ions pumping out (H+ use primary diffusion)
Questions and CORRECT Answers
5 compartments of the GI tract - CORRECT ANSWER - Oral cavity, esophagus, stomach,
small intestine and large intestine.
Name 4 accessory organs. - CORRECT ANSWER - Salivary glands, liver, gallbladder and
pancreas
Name at least 3 functions of the stomach. - CORRECT ANSWER - 1.Form chime
2.Store food
3.Secrete acid, pepsinogen & mucus
4.Initiates digestion of proteins and lipids
Kill bacteria
5.Absorb ethanol, some drugs and other small water-soluble compounds
What is secreted from G-cells - CORRECT ANSWER - Gastrin.
When G-cell release gastrin, it can go ECL cell to produce more histamine, or bind directly to the
parietal cell, and activiate cAmp.... The final goal is to stimulate more H+ pumping out
What is secreted from parietal cells - CORRECT ANSWER - Produce HCL and Intrinsic
factor (Absorb B12)
What is secreted from D cells - CORRECT ANSWER - Somatostatin
inhibitory the production of HCL
What is secreted from ECL cells(enterichromaffin-like cell) - CORRECT ANSWER - ECL
release histamine, then binds to H2 receptor
, What is secreted from Chief cells - CORRECT ANSWER - 1.pepsinogen(proenzyme), which
later on converts to Pepsin by HCL. Pepsin is an enzyme that breaks down protein to smaller
peptides.
2. Gastric Lipase splits fat (only remove one fatty acids but still)
What is Vagus nerve release? - CORRECT ANSWER - Vagus nerve release acetylcholine,
will either goes to ECL cell to produce histamine, or binds to acetylcholine (M) receptor.
summary diagram for HCL production in parietal cells - CORRECT ANSWER -
What is the main function of goblet cells? - CORRECT ANSWER - Mucin production
Name the 4 layers that comprise the wall of the gastrointestinal tract. What layer comes into
contact with food? - CORRECT ANSWER - 1. Mucosa
2. Submucosa
3. Muscularis
4. Serosa
*Mucosa is the layer that come into contact with food
Describe how parietal cells mediate acidification of the stomach. - CORRECT ANSWER -
step 1: CO2 diffuses into the cells, and the enzyme carbonic anhydrase catalyzes the reaction
between CO2 and water to form Carbonic Acid. H2CO3-.
Step 2: H2CO3 dissociates into bicarbonate ion (HCO3-) and H+.
Step 3: As HCO3- and H+ accumulates into the cell, HCO3- is ejected through the basal cell
membrane into the capillary blood by secondary active trans, in order to get CL- in
Step 4: ATP will then bind to the H+/K+ ATPase where the potassium knows are facilitated and
counter diffuse into the stomach lumen then come back into the parietal cell and exchange for
hydrogen ions pumping out (H+ use primary diffusion)
