IIN Gut Health & Microbiome 2 — Questions and Answers
Question 1: Which fermented food is traditionally made from salted, fermented cabbage and is rich in Lactobacillus bacteria?
- Kimchi
- Sauerkraut (Correct answer)
- Tempeh
- Miso
Correct answer: Sauerkraut
Sauerkraut is made from salted, fermented cabbage and contains Lactobacillus species that support gut microbiome diversity.
Question 2: The gut-brain axis communicates primarily through which nerve?
- Phrenic nerve
- Sciatic nerve
- Vagus nerve (Correct answer)
- Trigeminal nerve
Correct answer: Vagus nerve
The vagus nerve is the primary pathway of the gut-brain axis, transmitting signals bidirectionally between the enteric and central nervous systems.
Question 3: Approximately what percentage of the body's serotonin is produced in the gut?
- 10%
- 35%
- 70%
- 95% (Correct answer)
Correct answer: 95%
About 95% of the body's serotonin is produced by enterochromaffin cells in the gut, highlighting the gut's role in mood regulation.
Question 4: Which type of dietary fiber selectively feeds beneficial bacteria and is classified as a prebiotic?
- Cellulose
- Inulin (Correct answer)
- Lignin
- Chitin
Correct answer: Inulin
Inulin is a prebiotic fiber found in foods like chicory root and garlic that selectively stimulates growth of beneficial Bifidobacterium and Lactobacillus species.
Question 5: Intestinal permeability, sometimes called 'leaky gut,' refers to increased permeability of which structure?
- The mucus layer
- The tight junctions between epithelial cells (Correct answer)
- The intestinal villi
- The lamina propria
Correct answer: The tight junctions between epithelial cells
Leaky gut involves breakdown of tight junctions between intestinal epithelial cells, allowing undigested particles and toxins to pass into the bloodstream.
Question 6: Which short-chain fatty acid (SCFA) is the primary energy source for colonocytes?
- Acetate
- Propionate
- Butyrate (Correct answer)
- Lactate
Correct answer: Butyrate
Butyrate is the preferred energy substrate for colonocytes (colon lining cells) and also has anti-inflammatory and gut-protective properties.
Question 7: Which condition is characterized by an overgrowth of bacteria in the small intestine?
- Irritable Bowel Syndrome (IBS)
- Small Intestinal Bacterial Overgrowth (SIBO) (Correct answer)
- Crohn's disease
- Celiac disease
Correct answer: Small Intestinal Bacterial Overgrowth (SIBO)
SIBO occurs when bacteria that normally colonize the large intestine migrate and proliferate in the small intestine, causing bloating, gas, and malabsorption.
IIN Gut Health & Microbiome 2
Which fermented food is traditionally made from salted, fermented cabbage and is rich in Lactobacillus bacteria?