GI Tract All Lectures: Example Questions

Questions asked in class and made for the presentation material

Which cell secretes HCl?

Parietal cells of the stomach

How is hurricane/wind movement similar to simple diffusion?

A solute moves down a concentration gradient, and hurricanes move from high pressure to low

What is the role of carbonic anhydrase in any given cell?

Conversion of H2O and CO2 into carbonic acid

What is the role of the parietal cell in the stomach?

All of the above

What is the difference between GLUT2 and GLUT5?

GLUT2 is a from the basolateral membrane and aids in transport glucose, galactose and fructose, while GLUT5 is from the apical membrane, and only aids in transporting fructose

The rhythmic contractions of the alimentary canal that moves food forward is:

Peristalsis

What controls peristalsis?

Myenteric plexus

The network of nerves within the walls of the digestive tract that controls the movement and secretions of the digestive tract is the ___ nervous system.

Enteric

Identify the hormone secreted by the stomach that controls muscular contraction and secretions of the stomach

Gastrin

Accessory digestive organs include:

The gallbladder

Which of the following about CA is true:

All of the above

Identify the layers of the wall of the digestive tract from deepest to most superficial.

Mucosa, Submucosa, Muscularis, Serosa

Throughout the majority of the digestive tract the muscularis consists of ___ layers of ___ muscle

2;smooth

A 54-year-old man presents with concerns over increasing chest pain that is worse at night after eating. The physician refers him to an endoscopy clinic to visualize the esophagus, and a biopsy is taken from the distal portion of the esophagus. The pathology team reports evidence of cells that should not be there. Which of the following describes the findings of the pathology team?

Simple columnar epithelium was present instead of non-keratinized stratified squamous epithelium

You walk into a bakery and smell all of the wonderful smells of the breads and pastries. As a result, you become hungry and your stomach begins to “rumble“. This is a result of the ___ of digestive regulation.

Cephalic phase

Which of the following does NOT affect digestive tract functions?

All of the above affect digestive functions

Gastrin, which is released by stomach cells, causes ___

Stomach release of gastric juices

Which of the following is true?

The gastric mucosal barrier is protected by mucins that are continuously synthesized after being cleavved by pepsins

True or False: The fundus of the stomach contains chief cells which secrete pepsin

False

True or False: The pyloric sphincer is a ring of smooth muscle innervated by the facial and gastrovagal nerves

False

Which of the following is true about the ENS?

The myenteric plexus is associated with specific musclular control of the outer longitudinal and inner circular muscles of the GI tract

Which of the following is true?

The gastric mucosal barrier is protected by mucins that are continuously synthesized after being cleaved by pepsinogen

Which of the following statements is true?

All of the above are true

A 42-year-old man comes to his physician because of worsening epigastric pain.
Additionally, he reports having increasingly loose stools for the past 6 months and
recent weight loss of ~5 pounds. He notes that when he wakes in the morning, his
throat is often mildly sore. Results of endoscopy reveal multiple lesions in the
stomach and duodenum.

This patient’s pathology is secondary to the release of a substance that is normally
secreted from which of the following types of cells?

Parietal cells

Which of the following is responsible for initiating
peristalsis in the small intestine?

Intrinsic pacemaker cells (interstitial Cells of Cajal)

A 58-year-old man presents with new-onset hypertension. The clinician
prescribes him the calcium channel blocker Verapamil and councils him that
constipation is a possible adverse effect. By what mechanism does Verapamil
cause constipation?

Decreases GI motility

Which of the following best describes the primary role of the vagus
nerve in gastrointestinal motility?

It promotes smooth muscle contraction in the stomach and intestines

Which of the following comparisons is not correct?

Feces, non-digestible remains, bile and bacteria

Which organ will secrete bicarbonate to neutralize the acidity of chyme in the duodenum?

Pancreas

Which of the following hormones is paired correctly with its effects?

None of the above

Which of the following is/are produced by enteroendocrine cells of the duodenal wall?

Secretin and CCK

The two mechanisms of the parietal cell by which H+ is secreted into lumen of stomach and HCO3- into interstitial fluid/blood are

H+, K+ antiporter apical; Cl-, HCO3- antiporter basolateral

Which of the following substances binds to H2 receptors on parietal cells to stimulate acid secretion in the stomach?

Histamine

Which of the following best describes the role of the proton pump (H+/K+ ATPace) in parietal cells?

It pumps protons (H+) into the stomach lumen in exchange for potassium (K+)

A new research lab is trying to adjust the mechanism of action of various drugs affecting absorption. Their most recent experiment has been with a peptide that specifically blocks sodium-coupled transport proteins on the apical surface of enterocytes in the small intestine. What would most likely be seen in the lumen of the small intestine if a patient were administered this new drug?

Elevated levels of single amino acids, glucose, and galactose

Describe the full effects of lactase deficiency

A lactace deficiency is characterized by a non-absorption of lactose by lactase enzymes within the body. The areas of effect include the ____. Long-term, the in-digestibility of lactose will cause ___. Many adults will naturally lose lactase if milk is not regularity consumed.

The apical and basolateral enterocyte transporters for glucose and fructose are?

Apical - SGLT-1, GLUT-5; Basolateral - GLUT-2

When fats are broken down by lipase, ___ will be formed

Fatty acids and glycerol

Which of the following comparisons is NOT correct?

Maltose - lactase

How do MAMPs interact with enterocytes and bacteria?

Binds to the enterocyte to open a channel to let the bacteria enter the gut

What does the Gut-Associated Lymphoid Tissue (GALT) release to monitor the pathogenic bacteria?

Lymphocytes

When the brain is placed under stress, the hypothalamus releases Corticotropin Releasing hormone (CRH). What does CRH act on to release what?

Anterior pituitary, Adrenocorticotrophic Hormone

What is the benefit of using synbiotics versus eating probiotic-rich foods?

Having a specialized formula of what is needed for the patient’s gut microbiome

Which of the following best explains how gut dysbiosis initiates a cascade leading to neurodegeneration via host pattern-recognition receptor (PRR) signaling?

A. Dysbiosis increases beneficial metabolite production, which activates PRRs on intestinal epithelial cells and reduces NF-κB signaling, leading to impaired synaptic pruning.
B. Increased intestinal permeability allows microbial components (PAMPs/DAMPs) to interact with PRRs, activating inflammatory pathways, with repeated long-term stimulation resulting in chronic neuroinflammation and protein misfolding.
C. Enrichment of Firmicutes enhances autophagic flux and downregulates cytokine production, thereby promoting α-synuclein aggregation.
D. Dysbiosis suppresses DAMP recognition by microglia, reducing type I interferon signaling and causing excitotoxicity via glutamatergic hyperactivation.

Which of the following best describes the primary mechanistic cascade through which gut dysbiosis promotes neurodegeneration?

A. Dysbiosis reduces vagal tone, which directly increases hippocampal neurogenesis and promotes compensatory neuroinflammation that becomes pathological when metabolites like SCFA levels rise.
B. Dysbiosis increases intestinal and BBB permeability, enabling microbial metabolites to activate PRRs (e.g., TLRs), which initiate chronic immune signaling pathways (e.g., NF-κB, inflammasome), leading to neuroinflammation, oxidative stress, and misfolded protein aggregation.
C. Dysbiosis primarily suppresses MyD88-dependent innate signaling, reducing the host’s ability to clear pathogens and resulting in compensatory α-synuclein overexpression in the gut.
D. Dysbiosis causes increased serotonin synthesis in enterochromaffin cells, increasing CNS excitotoxicity and initiating autophagic defects that promote β-amyloid fibrillization.

How does estrogen and progesterone aid in the health of Lactobacillus?

Decreases vaginal pH

How do eating disorders impact the menstrual cycle?

All of the above

What role does vitamin A play in children’s gut microbiota?

Vitamin A supplementation enhances mucosal immunity

What below is true in regards to Anorexia Nervosa?

All of the above

What types of cells are included in the pancreatic islets?

Beta Cells, Alpha Cells, Delta Cells, F Cells, Capillary Cells

What complex micro-organisms make up the pancreatic islets?

Endocrine, Neuronal, Vascular, Supporting Cells

Alpha cells release ___, especially during hypoglycemic conditions.

Glucagon

___ cells near ___ cells express more GLP1r mRNA than other ___ cells

Alpha;Beta;Beta

Surface Plasmon Resonance (SPR) allows for ___

Single protein visualization

The pancreas influences other organ systems throughout the body. The communication inside the pancreas influences ___ inside the body.

Blood glucose control