Which disorder would most directly interfere with the emulsification of fats?

Answer Explanation

D) gallstones

- Correct: Gallstones would most directly interfere with the emulsification of fats. Emulsification of fats is primarily facilitated by bile, a digestive fluid produced by the liver and stored in the gallbladder. Gallstones are hardened deposits that form in the gallbladder, often consisting of cholesterol or bilirubin. These stones can obstruct the flow of bile from the gallbladder into the small intestine, impairing the emulsification of fats and leading to difficulties in fat digestion and absorption. This obstruction can result in symptoms such as abdominal pain, nausea, and indigestion.

A) bronchitis

- Incorrect: Bronchitis is inflammation of the bronchial tubes in the lungs and does not directly interfere with the emulsification of fats in the digestive system.

B) gout

- Incorrect: Gout is a form of arthritis characterized by the accumulation of uric acid crystals in the joints, typically affecting the feet. It does not directly interfere with the emulsification of fats in the digestive system.

C) goiter

- Incorrect: Goiter is an abnormal enlargement of the thyroid gland in the neck, often due to iodine deficiency or thyroid disorders. It does not directly interfere with the emulsification of fats in the digestive system.

Answer Explanation

b) iron

- Correct: Iron is mainly absorbed in the duodenum, particularly in its proximal portion. Iron absorption occurs through active transport mechanisms facilitated by specialized transport proteins in the duodenal epithelial cells. Once absorbed, iron can be transported into the bloodstream and utilized for various physiological functions, including the production of hemoglobin and other iron-containing proteins.

a) glucose

- Incorrect: Glucose is primarily absorbed in the small intestine, but its absorption occurs mainly in the jejunum and ileum rather than the duodenum. Glucose is absorbed through facilitated diffusion and active transport mechanisms in the epithelial cells lining the small intestine.

c) sodium

- Incorrect: Sodium is absorbed throughout the small intestine, including the duodenum, jejunum, and ileum. Its absorption occurs through active transport mechanisms in the epithelial cells lining the intestinal mucosa, primarily in conjunction with glucose and other nutrients.

d) water

- Incorrect: Absorption of water indeed takes place in the large intestine, particularly in the colon.

Answer Explanation

Enzymes are proteins that catalyze specific biochemical reactions in living organisms.

The production of enzymes is regulated by gene expression, where specific genes are activated (expressed) to produce particular enzymes in different cells or tissues.

In this case, the gene responsible for coding the enzyme pepsin is expressed in the cells of the stomach, leading to the production of pepsin in the stomach.

Conversely, the gene for trypsin is expressed in the cells of the small intestine, resulting in the production of trypsin in the small intestine.

Therefore, the reason that the stomach and small intestine produce different enzymes is due to the differential gene expression in these respective tissues.