| 1 | Bile digests fats enzymatically. | FALSE. Bile SALTS emulsify fats (break into smaller droplets) without any enzymatic action. Pancreatic lipase performs actual fat digestion. |
| 2 | Enterokinase is secreted by the pancreas. | FALSE. Enterokinase is secreted by the DUODENAL MUCOSA (intestinal origin, not pancreatic). |
| 3 | Salivary amylase continues to work in the stomach. | FALSE. Salivary amylase is inactivated by stomach acid (pH 1.5–2.0); its optimum is pH 6.8. |
| 4 | Bile is produced in the gallbladder. | FALSE. Bile is PRODUCED by the LIVER and STORED (concentrated) in the GALLBLADDER. |
| 5 | Glucose is absorbed into lacteals. | FALSE. Glucose is absorbed by active transport (SGLT) into BLOOD capillaries. Only FATS (as chylomicrons) go into lacteals. |
| 6 | The large intestine is the main site of nutrient absorption. | FALSE. The SMALL INTESTINE is the main site of nutrient absorption. The large intestine absorbs only water and minerals. |
| 7 | HCl activates trypsinogen to trypsin. | FALSE. ENTEROKINASE (from duodenal mucosa) activates trypsinogen to trypsin. HCl activates PEPSINOGEN to PEPSIN. |
| 8 | Kwashiorkor and Marasmus both cause extreme muscle wasting. | FALSE. Kwashiorkor causes oedema with RELATIVELY PRESERVED fat/muscle. Marasmus causes EXTREME wasting without oedema. |
| 9 | Trypsin is secreted in its active form by the pancreas. | FALSE. Trypsin is secreted as inactive TRYPSINOGEN. Only enterokinase in the duodenum activates it to trypsin. |
| 10 | The stomach is the primary site of carbohydrate digestion. | FALSE. The stomach contains no amylase; it's the site of PROTEIN digestion. Starch digestion occurs mainly in the duodenum (pancreatic amylase) and brush border (maltase). |
| 11 | Fatty acids reach the liver before entering systemic circulation. | FALSE. Fatty acids (as chylomicrons) travel via LACTEALS → THORACIC DUCT → left subclavian vein, BYPASSING the liver. Glucose and amino acids go via portal vein → liver first. |
| 12 | Pepsin works in the small intestine. | FALSE. Pepsin is optimal at pH 1.5–2.0 (stomach). In the duodenum, bicarbonate raises pH to ~7–8, inactivating pepsin. Protein digestion continues with trypsin and chymotrypsin. |
| 13 | Pancreatic juice is acidic. | FALSE. Pancreatic juice is ALKALINE (rich in bicarbonate, pH ~8) — specifically designed to neutralize acidic chyme. |
| 14 | Secretin stimulates gallbladder to release bile. | FALSE. SECRETIN stimulates pancreatic BICARBONATE secretion. CCK stimulates GALLBLADDER contraction and bile release. |
| 15 | All brush border enzymes are secreted into the intestinal lumen. | FALSE. Brush border enzymes are MEMBRANE-BOUND on the enterocyte surface — they are not secreted. Final digestion occurs directly at the absorption site. |
| 16 | Vitamin K is obtained only from diet; gut bacteria don't contribute. | FALSE. Gut bacteria in the large intestine synthesize vitamin K2 (menaquinone). Antibiotic use can deplete this supply. |
| 17 | The pyloric sphincter prevents backflow from the small intestine into the stomach. | PARTIALLY FALSE. The pyloric sphincter primarily regulates the rate of chyme entry into the duodenum. The ileocaecal valve prevents backflow from large to small intestine. |
| 18 | Proteins are only digested in the stomach by pepsin. | FALSE. Protein digestion begins in the stomach (pepsin) but is COMPLETED in the small intestine by trypsin, chymotrypsin, elastase, carboxypeptidase, aminopeptidase, and dipeptidases. |
| 19 | The vomiting reflex is controlled by the cerebral cortex. | FALSE. The vomiting centre is located in the MEDULLA OBLONGATA (brainstem), not the cerebral cortex. |
| 20 | Mastication (chewing) has no effect on the rate of chemical digestion. | FALSE. Chewing breaks food into smaller particles, dramatically increasing the surface area exposed to digestive enzymes — significantly accelerating chemical digestion. |