Follow the Food
What is the first organ food enters?
Mouth
What does the stomach do to food?
Breaks it down mechanically (churning) and chemically (acid + enzymes)
Digestion starts before you take a bite.
True (smelling food triggers saliva + enzymes)
During the fed state, what organ signals the stomach that food is coming?
The mouth.
Which organ is about 22 feet long?
The small intestine.
What tube connects the mouth to the stomach?
Esophagus
What does the liver produce to help digest fats?
Bile
The gallbladder makes bile.
False
When the esophagus is unused, why does swallowing sometimes feel slower or heavier?
Because the esophagus muscles weaken from underuse, making peristalsis harder.
What is the only organ part that can absorb B12?
The Illeum
Put these in order: Jejunum → Stomach → Duodenum → Illeum.
Stomach → Duodenum → Jejunum → Illeum
What does the pancreas release to help break down carbs, proteins, and fats?
Digestive enzymes
The liver is part of the digestive system.
True (it supports digestion even though food doesn’t pass through it)
During refeeding, why might someone feel more burping, reflux, or cramping?
Because acid and enzyme production ramp back up, and stomach/intestinal muscles start working harder again.
(ill take one of these answers)
How many sphincters does the digestive system have?
5 major sphincters
What is the wave‑like muscle contractions that push food forward?
Peristalsis
Where does carbohydrate digestion start?
The mouth.
The large intestine absorbs protein, carbs, fat, and/or vitamins.
False — It mainly absorbs water and electrolytes, not nutrients.
Explain ONE of the reasons why fullness feels unpredictable or uncomfortable during periods of long unuse.
Low stomach acid + weak stomach muscles make food sit heavier and longer.
Hormone signaling becomes irregular, so fullness cues fire at the wrong times or too strongly.
(ill take either one)
What vitamins does you gut microbiome make?
Vitamin K and some B vitamins
What TWO major processes happen in the small intestine that do NOT happen in the stomach?
Most nutrient absorption
Enzyme breakdown from accessory organs
What is the primary site of digestion and the primary site of absorption in the SI?
Duodenum
Jejunum
The esophagus performs both mechanical and chemical digestion.
False — It only performs mechanical movement (peristalsis).
During starvation, why does fat digestion become harder and sometimes cause nausea or greasy stools?
Because bile production decreases, so the gallbladder sends less bile to the duodenum, making fat harder to break down and absorb.
Which part of the digestive system contains over 100 million neurons and is often called the “second brain”?
The gut
Fun fact: it has more neurons than a cats brain.