7 Digestive System Physiology Free Online FlashCards

How do digestion and absorption differ?

Digestion breaks food into smaller molecules; absorption moves those products across the gut lining into the body.

Why does mechanical digestion help chemical digestion?

Mechanical processing increases food’s surface area, helping chemical digestion act on it more effectively.

How do peristalsis and segmentation differ?

Peristalsis propels contents forward; segmentation repeatedly mixes them with secretions and brings them into contact with the intestinal surface.

What does salivary amylase begin digesting?

Salivary amylase begins the chemical digestion of starch in the mouth.

What roles do stomach acid and pepsin play?

Hydrochloric acid helps denature proteins, and pepsin begins their digestion in the stomach.

What does pancreatic bicarbonate do in the small intestine?

Pancreatic bicarbonate neutralizes acidic chyme, creating conditions suitable for intestinal enzymes.

How does the small intestine provide a large absorption surface?

Folds, villi, and microvilli create a large absorptive surface in the small intestine.

Where do most absorbed sugars and amino acids go first?

Most absorbed carbohydrates and proteins enter blood capillaries and travel first to the liver through the hepatic portal vein.

What does secretin signal the pancreas to secrete?

Acidic chyme in the duodenum triggers secretin release; secretin stimulates pancreatic bicarbonate secretion.

How does insulin help manage rising blood glucose after a meal?

After a meal, insulin supports glucose uptake and use by tissues and promotes storage of excess energy.

Why is intrinsic factor important?

Intrinsic factor is needed for vitamin B₁₂ absorption later in the small intestine.

How does bile aid fat digestion?

Bile salts emulsify fats and help their digestion and absorption, but bile is not an enzyme.