Question

the type of digestion in the stomach that alters chemical bonds, producing new and different molecules is
a. mechanical digestion by smooth muscles that increase the surface area for better enzyme action
b. chemical digestion by pepsin on carbohydrates
c. mechanical digestion by smooth muscles producing many smaller particles
d. chemical digestion by pepsin acting on the food group proteins
most chemical digestion occurs in the
a. duodenum
b. large intestine
c. ilium
d. jejunum

Explanation:

1. In the stomach, pepsin is an enzyme that acts on proteins to break them down chemically, altering chemical bonds and producing new molecules. Mechanical digestion in the stomach involves muscle - contractions but does not change chemical bonds. Pepsin does not act on carbohydrates.
2. Most chemical digestion occurs in the duodenum, the first part of the small intestine, where many digestive enzymes from the pancreas and bile from the liver are released to break down food.

Answer:

1. D. chemical digestion by pepsin acting on the food group proteins
2. A. duodenum